diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.cs
index bb9e2298f1cc..c7e2a92fc95b 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.cs
@@ -273,7 +273,7 @@ public override AmazonWebServiceResponse Unmarshall(XmlUnmarshallerContext conte
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            ErrorResponse errorResponse = ErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
 ");
             
             #line 121 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryEC2ResponseUnmarshaller.tt"
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.tt
index 378de529009f..6207a8edd2bf 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryEC2ResponseUnmarshaller.tt
@@ -117,7 +117,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            ErrorResponse errorResponse = ErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
 <#
     foreach (var exception in this.Operation.Exceptions)
     {
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.cs
index 01aa30211aa1..1ddd526d3a47 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.cs
@@ -18,7 +18,7 @@ namespace ServiceClientGenerator.Generators.Marshallers
     /// Class to produce the template output
     /// </summary>
     
-    #line 1 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+    #line 1 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "17.0.0.0")]
     public partial class AWSQueryExceptionUnmarshaller : BaseResponseUnmarshaller
     {
@@ -29,7 +29,7 @@ public partial class AWSQueryExceptionUnmarshaller : BaseResponseUnmarshaller
         public override string TransformText()
         {
             
-            #line 6 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 6 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
     AddLicenseHeader();
 
@@ -40,7 +40,7 @@ public override string TransformText()
             #line hidden
             this.Write("#pragma warning disable CS0612,CS0618\r\nnamespace ");
             
-            #line 12 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 12 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
@@ -48,21 +48,21 @@ public override string TransformText()
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n    /// <summary>\r\n    /// Response U" +
                     "nmarshaller for ");
             
-            #line 15 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 15 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" operation\r\n    /// </summary>  \r\n    public class ");
             
-            #line 17 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller : IErrorResponseUnmarshaller<");
+            this.Write("Unmarshaller : IXmlErrorResponseUnmarshaller<");
             
-            #line 17 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -72,7 +72,7 @@ public override string TransformText()
                     "\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n  " +
                     "      public ");
             
-            #line 24 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 24 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -90,7 +90,7 @@ public override string TransformText()
         /// <returns></returns>
         public ");
             
-            #line 35 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 35 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -98,14 +98,14 @@ public override string TransformText()
             this.Write(" Unmarshall(XmlUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse" +
                     " errorResponse)\r\n        {\r\n            ");
             
-            #line 37 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 37 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" response = new ");
             
-            #line 37 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 37 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -125,7 +125,7 @@ public override string TransformText()
                 {
 ");
             
-            #line 50 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
     if(this.Structure != null)
     {
@@ -138,14 +138,14 @@ public override string TransformText()
             #line hidden
             this.Write("                    if (context.TestExpression(\"");
             
-            #line 57 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(testExpression));
             
             #line default
             #line hidden
             this.Write("\", targetDepth))\r\n                    {\r\n");
             
-            #line 59 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 59 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
             if (member.IsMap || member.IsList)
             {
@@ -155,42 +155,42 @@ public override string TransformText()
             #line hidden
             this.Write("                        if (response.");
             
-            #line 63 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 63 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(MemberAccessorFor(member.PropertyName)));
             
             #line default
             #line hidden
             this.Write(" == null)\r\n                        {\r\n                            response.");
             
-            #line 65 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 65 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(MemberAccessorFor(member.PropertyName)));
             
             #line default
             #line hidden
             this.Write(" = new ");
             
-            #line 65 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 65 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
             #line hidden
             this.Write("();\r\n                        }\r\n                        var item = ");
             
-            #line 67 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(".Unmarshall(context);\r\n                        response.");
             
-            #line 68 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(MemberAccessorFor(member.PropertyName)));
             
             #line default
             #line hidden
             this.Write(".Add(item);\r\n");
             
-            #line 69 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 69 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
             }
             else
@@ -201,21 +201,21 @@ public override string TransformText()
             #line hidden
             this.Write("                        response.");
             
-            #line 74 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 74 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(MemberAccessorFor(member.PropertyName)));
             
             #line default
             #line hidden
             this.Write(" = ");
             
-            #line 74 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 74 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(".Unmarshall(context);\r\n");
             
-            #line 75 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
             }
 
@@ -224,7 +224,7 @@ public override string TransformText()
             #line hidden
             this.Write("                    }\r\n");
             
-            #line 79 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 79 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
         }
     }
@@ -234,7 +234,7 @@ public override string TransformText()
             #line hidden
             this.Write("                }\r\n            }\r\n            return response;\r\n        }\r\n\r\n");
             
-            #line 88 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+            #line 88 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
     this.AddStructureSingletonMethod();
 
@@ -245,7 +245,7 @@ public override string TransformText()
             return this.GenerationEnvironment.ToString();
         }
         
-        #line 94 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
+        #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryExceptionUnmarshaller.tt"
 
 // if the result fields have been wrapped in a subordinate structure, wire the accessor
 // to use it when addressing a member
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.tt
index 0f17743a821d..ea6fd3f5d926 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryExceptionUnmarshaller.tt
@@ -14,7 +14,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for <#=this.UnmarshallerBaseName #> operation
     /// </summary>  
-    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IErrorResponseUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>
+    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IXmlErrorResponseUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.cs
index 65d9a560f376..9fca6b480d3f 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.cs
@@ -316,7 +316,7 @@ public override AmazonWebServiceResponse Unmarshall(XmlUnmarshallerContext conte
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            ErrorResponse errorResponse = ErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.tt
index 772e6bc50820..f5f0c8d075a9 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryResponseUnmarshaller.tt
@@ -138,7 +138,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            ErrorResponse errorResponse = ErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.cs
index 43daa547babb..16f6324eb5b0 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.cs
@@ -18,7 +18,7 @@ namespace ServiceClientGenerator.Generators.Marshallers
     /// Class to produce the template output
     /// </summary>
     
-    #line 1 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+    #line 1 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "17.0.0.0")]
     public partial class AWSQueryStructureUnmarshaller : BaseResponseUnmarshaller
     {
@@ -29,7 +29,7 @@ public partial class AWSQueryStructureUnmarshaller : BaseResponseUnmarshaller
         public override string TransformText()
         {
             
-            #line 6 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 6 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
     AddLicenseHeader();
 
@@ -40,7 +40,7 @@ public override string TransformText()
             #line hidden
             this.Write("#pragma warning disable CS0612,CS0618\r\nnamespace ");
             
-            #line 12 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 12 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
@@ -48,52 +48,45 @@ public override string TransformText()
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n    /// <summary>\r\n    /// Response U" +
                     "nmarshaller for ");
             
-            #line 15 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 15 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" Object\r\n    /// </summary>  \r\n    public class ");
             
-            #line 17 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller : IUnmarshaller<");
+            this.Write("Unmarshaller : IXmlUnmarshaller<");
             
-            #line 17 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write(", XmlUnmarshallerContext>, IUnmarshaller<");
+            this.Write(", XmlUnmarshallerContext>\r\n    {\r\n        /// <summary>\r\n        /// Unmarshaller" +
+                    " the response from the service to the response class.\r\n        /// </summary>  \r" +
+                    "\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n  " +
+                    "      public ");
             
-            #line 17 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(", JsonUnmarshallerContext>\r\n    {\r\n        /// <summary>\r\n        /// Unmarshalle" +
-                    "r the response from the service to the response class.\r\n        /// </summary>  " +
-                    "\r\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n " +
-                    "       public ");
-            
-            #line 24 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 24 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" Unmarshall(XmlUnmarshallerContext context)\r\n        {\r\n            ");
             
-            #line 26 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 26 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" unmarshalledObject = new ");
             
-            #line 26 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 26 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -111,7 +104,7 @@ public override string TransformText()
                 {
 ");
             
-            #line 37 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 37 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
     if(this.Structure != null)
     {
@@ -124,7 +117,7 @@ public override string TransformText()
             #line hidden
             this.Write("                    if (context.TestExpression(\"");
             
-            #line 44 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 44 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(testExpression));
             
             #line default
@@ -132,14 +125,14 @@ public override string TransformText()
             this.Write("\", targetDepth))\r\n                    {\r\n                        var unmarshaller" +
                     " = ");
             
-            #line 46 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 46 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(";\r\n");
             
-            #line 47 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 47 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
             if (member.IsMap || member.IsList)
             {
@@ -149,7 +142,7 @@ public override string TransformText()
             #line hidden
             this.Write("                        if (unmarshalledObject.");
             
-            #line 51 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
@@ -157,14 +150,14 @@ public override string TransformText()
             this.Write(" == null)\r\n                        {\r\n                            unmarshalledObj" +
                     "ect.");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 53 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = new ");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 53 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
@@ -172,14 +165,14 @@ public override string TransformText()
             this.Write("();\r\n                        }\r\n                        var item = unmarshaller.U" +
                     "nmarshall(context);\r\n                        unmarshalledObject.");
             
-            #line 56 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 56 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(".Add(item);\r\n");
             
-            #line 57 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
             }
             else
@@ -190,14 +183,14 @@ public override string TransformText()
             #line hidden
             this.Write("                        unmarshalledObject.");
             
-            #line 62 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 62 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = unmarshaller.Unmarshall(context);\r\n");
             
-            #line 63 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 63 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
             }
 
@@ -206,7 +199,7 @@ public override string TransformText()
             #line hidden
             this.Write("                        continue;\r\n                    }\r\n");
             
-            #line 68 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
         }
     }
@@ -224,22 +217,9 @@ public override string TransformText()
             return unmarshalledObject;
         }
 
-        /// <summary>
-        /// Unmarshaller error response to exception.
-        /// </summary>  
-        /// <param name=""context""></param>
-        /// <returns></returns>
-        public ");
-            
-            #line 87 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(" Unmarshall(JsonUnmarshallerContext context)\r\n        {\r\n            return null;" +
-                    "\r\n        }\r\n\r\n\r\n");
+");
             
-            #line 93 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
+            #line 82 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\AWSQueryStructureUnmarshaller.tt"
 
     this.AddStructureSingletonMethod();
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.tt
index d5ca583c4f05..15453b45a2c4 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/AWSQueryStructureUnmarshaller.tt
@@ -14,7 +14,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for <#=this.UnmarshallerBaseName #> Object
     /// </summary>  
-    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>, IUnmarshaller<<#=this.UnmarshallerBaseName #>, JsonUnmarshallerContext>
+    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IXmlUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
@@ -79,17 +79,6 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
             return unmarshalledObject;
         }
 
-        /// <summary>
-        /// Unmarshaller error response to exception.
-        /// </summary>  
-        /// <param name="context"></param>
-        /// <returns></returns>
-        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context)
-        {
-            return null;
-        }
-
-
 <#
     this.AddStructureSingletonMethod();
 #>
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.cs
index cfb8e819b070..a76b07e68f69 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.cs
@@ -18,7 +18,7 @@ namespace ServiceClientGenerator.Generators.Marshallers
     /// Class to produce the template output
     /// </summary>
     
-    #line 1 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+    #line 1 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "17.0.0.0")]
     public partial class JsonRPCExceptionUnmarshaller : BaseResponseUnmarshaller
     {
@@ -29,7 +29,7 @@ public partial class JsonRPCExceptionUnmarshaller : BaseResponseUnmarshaller
         public override string TransformText()
         {
             
-            #line 6 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 6 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
     AddLicenseHeader();
 
@@ -38,10 +38,10 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("using ThirdParty.Json.LitJson;\r\n\r\n#pragma warning disable CS0612,CS0618\r\nnamespac" +
-                    "e ");
+            this.Write("using System.Text.Json;\r\nusing Amazon.Util;\r\n#pragma warning disable CS0612,CS061" +
+                    "8\r\nnamespace ");
             
-            #line 14 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 14 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
@@ -49,38 +49,43 @@ public override string TransformText()
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n    /// <summary>\r\n    /// Response U" +
                     "nmarshaller for ");
             
-            #line 17 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" Object\r\n    /// </summary>  \r\n    public class ");
             
-            #line 19 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller : IErrorResponseUnmarshaller<");
+            this.Write("Unmarshaller : IJsonErrorResponseUnmarshaller<");
             
-            #line 19 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write(", JsonUnmarshallerContext>\r\n    {\r\n        /// <summary>\r\n        /// Unmarshalle" +
-                    "r the response from the service to the response class.\r\n        /// </summary>  " +
-                    "\r\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n " +
-                    "       public ");
+            this.Write(@", JsonUnmarshallerContext>
+    {
+        /// <summary>
+        /// Unmarshaller the response from the service to the response class.
+        /// </summary>  
+        /// <param name=""context""></param>
+        /// <param name=""reader""></param>
+        /// <returns></returns>
+        public ");
             
-            #line 26 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 27 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write(@" Unmarshall(JsonUnmarshallerContext context)
+            this.Write(@" Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -88,18 +93,20 @@ public override string TransformText()
         /// </summary>  
         /// <param name=""context""></param>
         /// <param name=""errorResponse""></param>
+        /// <param name=""reader""></param>
         /// <returns></returns>
         public ");
             
-            #line 37 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorRespons" +
-                    "e errorResponse)\r\n        {\r\n            context.Read();\r\n\r\n");
+                    "e errorResponse, ref StreamingUtf8JsonReader reader)\r\n        {\r\n            con" +
+                    "text.Read(ref reader);\r\n\r\n");
             
-            #line 41 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 43 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
             if  (this.Config.ServiceModel.IsAwsQueryCompatible)
             {
@@ -110,14 +117,14 @@ public override string TransformText()
             #line hidden
             this.Write("            ");
             
-            #line 46 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" unmarshalledObject = new ");
             
-            #line 46 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -125,7 +132,7 @@ public override string TransformText()
             this.Write("(errorResponse.Message, errorResponse.InnerException,\r\n                errorType," +
                     " errorCode, errorResponse.RequestId, errorResponse.StatusCode);\r\n");
             
-            #line 48 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
             }
             else
@@ -136,14 +143,14 @@ public override string TransformText()
             #line hidden
             this.Write("            ");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 55 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" unmarshalledObject = new ");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 55 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -152,7 +159,7 @@ public override string TransformText()
                     "nse.Type, errorResponse.Code, errorResponse.RequestId, errorResponse.StatusCode)" +
                     ";\r\n");
             
-            #line 55 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
             }
 
@@ -160,9 +167,9 @@ public override string TransformText()
             #line default
             #line hidden
             this.Write("        \r\n            int targetDepth = context.CurrentDepth;\r\n            while " +
-                    "(context.ReadAtDepth(targetDepth))\r\n            {\r\n");
+                    "(context.ReadAtDepth(targetDepth, ref reader))\r\n            {\r\n");
             
-            #line 62 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 64 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
     if(this.Structure != null)
     {
@@ -174,29 +181,29 @@ public override string TransformText()
             #line hidden
             this.Write("                if (context.TestExpression(\"");
             
-            #line 68 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 70 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
             
             #line default
             #line hidden
             this.Write("\", targetDepth))\r\n                {\r\n                    var unmarshaller = ");
             
-            #line 70 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 72 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(";\r\n                    unmarshalledObject.");
             
-            #line 71 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 73 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
-            this.Write(" = unmarshaller.Unmarshall(context);\r\n                    continue;\r\n            " +
-                    "    }\r\n");
+            this.Write(" = unmarshaller.Unmarshall(context, ref reader);\r\n                    continue;\r\n" +
+                    "                }\r\n");
             
-            #line 74 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 76 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
         }
     }
@@ -206,7 +213,7 @@ public override string TransformText()
             #line hidden
             this.Write("            }\r\n          \r\n            return unmarshalledObject;\r\n        }\r\n\r\n");
             
-            #line 83 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
+            #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCExceptionUnmarshaller.tt"
 
     this.AddStructureSingletonMethod();
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.tt
index 97ebdf03a760..2c75b5a2d328 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCExceptionUnmarshaller.tt
@@ -8,24 +8,25 @@
 
     AddCommonUsingStatements();
 #>
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for <#=this.UnmarshallerBaseName #> Object
     /// </summary>  
-    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IErrorResponseUnmarshaller<<#=this.UnmarshallerBaseName #>, JsonUnmarshallerContext>
+    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IJsonErrorResponseUnmarshaller<<#=this.UnmarshallerBaseName #>, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context)
+        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -33,10 +34,11 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
 <#
             if  (this.Config.ServiceModel.IsAwsQueryCompatible)
@@ -57,7 +59,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 #>
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
 <#
     if(this.Structure != null)
@@ -68,7 +70,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
                 if (context.TestExpression("<#=member.MarshallName#>", targetDepth))
                 {
                     var unmarshaller = <#= member.DetermineTypeUnmarshallerInstantiate() #>;
-                    unmarshalledObject.<#=member.PropertyName#> = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.<#=member.PropertyName#> = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
 <#
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.cs
index 85a51a68f195..0189b2265863 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.cs
@@ -38,31 +38,31 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("using System.Text.Json;\r\nusing System.Buffers;\r\n#pragma warning disable CS0612,CS" +
-                    "0618\r\nnamespace ");
+            this.Write("using System.Text.Json;\r\nusing System.Buffers;\r\n#if !NETFRAMEWORK\r\nusing ThirdPar" +
+                    "ty.RuntimeBackports;\r\n#endif\r\n#pragma warning disable CS0612,CS0618\r\nnamespace ");
             
-            #line 14 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
             #line hidden
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n\t/// <summary>\r\n\t/// ");
             
-            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 20 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
             #line hidden
             this.Write(" Request Marshaller\r\n\t/// </summary>       \r\n\tpublic class ");
             
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 22 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
             #line hidden
             this.Write("RequestMarshaller : IMarshaller<IRequest, ");
             
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 22 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
@@ -78,7 +78,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
         {
             return this.Marshall((");
             
-            #line 28 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 31 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
@@ -88,7 +88,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
                     " name=\"publicRequest\"></param>\r\n        /// <returns></returns>\r\n\t\tpublic IReque" +
                     "st Marshall(");
             
-            #line 36 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
@@ -96,14 +96,14 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             this.Write("Request publicRequest)\r\n\t\t{\r\n\t\t\tIRequest request = new DefaultRequest(publicReque" +
                     "st, \"");
             
-            #line 38 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 41 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
             #line hidden
             this.Write("\");\r\n");
             
-            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 42 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
    SetCompressionAlgorithmEncoding(this.Operation);
 
@@ -115,21 +115,21 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\tstring target = \"");
             
-            #line 45 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ServiceModel.TargetPrefix));
             
             #line default
             #line hidden
             this.Write(".");
             
-            #line 45 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
             #line hidden
             this.Write("\";\r\n\t\t\trequest.Headers[\"X-Amz-Target\"] = target;\r\n");
             
-            #line 47 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 	}
 	if (this.Operation.HttpMethod != "GET" && this.Operation.HttpMethod != "DELETE")
@@ -143,14 +143,14 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.Headers[\"Content-Type\"] = \"");
             
-            #line 55 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 58 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ServiceModel.Customizations.OverrideContentType));
             
             #line default
             #line hidden
             this.Write("\";\r\n");
             
-            #line 56 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 59 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 		else if (this.Config.ServiceModel.Type != ServiceType.Rest_Json)
@@ -161,14 +161,14 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.Headers[\"Content-Type\"] = \"application/x-amz-json-");
             
-            #line 61 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 64 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ServiceModel.JsonVersion));
             
             #line default
             #line hidden
             this.Write("\";\r\n");
             
-            #line 62 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 65 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 		else if (this.Operation.RequestHasBodyMembers || this.Operation.RequestPayloadMember != null)
@@ -179,7 +179,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.Headers[\"Content-Type\"] = \"application/json\";\r\n");
             
-            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 71 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 	}
@@ -189,21 +189,21 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("            request.Headers[Amazon.Util.HeaderKeys.XAmzApiVersion] = \"");
             
-            #line 72 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ServiceModel.APIVersion));
             
             #line default
             #line hidden
             this.Write("\";\r\n            request.HttpMethod = \"");
             
-            #line 73 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 76 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.HttpMethod));
             
             #line default
             #line hidden
             this.Write("\";\r\n\r\n");
             
-            #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 78 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 	var requestStructure = this.Operation.RequestStructure;
 	
@@ -221,14 +221,14 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.ResourcePath = \"");
             
-            #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 90 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.RequestUri));
             
             #line default
             #line hidden
             this.Write("\";\r\n");
             
-            #line 88 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 91 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
   
 
     var payload = this.Operation.RequestPayloadMember;
@@ -240,16 +240,16 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             
             #line default
             #line hidden
-            this.Write(@"#if NETCOREAPP3_1_OR_GREATER
-			ArrayBufferWriter<byte> arrayBufferWriter = new ArrayBufferWriter<byte>();
-			using Utf8JsonWriter writer = new Utf8JsonWriter(arrayBufferWriter);
+            this.Write(@"#if !NETFRAMEWORK
+			using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+			using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
 #else
             using var memoryStream = new MemoryStream();
 			using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
 #endif
 ");
             
-            #line 103 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 106 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 		
 		if (shouldMarshallPayload)
 		{
@@ -259,7 +259,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\tvar context = new JsonMarshallerContext(request, writer);\r\n");
             
-            #line 108 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 111 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 		
 			ProcessStructure(0, "publicRequest." + payload.PropertyName, payload.Shape);
 
@@ -268,7 +268,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\twriter.Flush();\r\n");
             
-            #line 112 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 115 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 		else
@@ -280,7 +280,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             this.Write("\t\t\twriter.WriteStartObject();\r\n\t\t\tvar context = new JsonMarshallerContext(request" +
                     ", writer);\r\n");
             
-            #line 119 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 		
 			ProcessMembers(0, "publicRequest", this.Operation.RequestBodyMembers);
 
@@ -289,18 +289,18 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\twriter.WriteEndObject();\r\n\t\t\twriter.Flush();\r\n");
             
-            #line 124 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 127 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 
             
             #line default
             #line hidden
-            this.Write("#if NETCOREAPP3_1_OR_GREATER\r\n            request.Content = arrayBufferWriter.Wri" +
-                    "ttenMemory.ToArray();\r\n#else\r\n\t\t\trequest.Content = memoryStream.ToArray();\r\n#end" +
-                    "if\r\n");
+            this.Write("\t\t\t// ToArray() must be called here because aspects of sigv4 signing require a by" +
+                    "te array\r\n#if !NETFRAMEWORK\r\n\t\t\trequest.Content = arrayPoolBufferWriter.WrittenM" +
+                    "emory.ToArray();\r\n#else\r\n\t\t\trequest.Content = memoryStream.ToArray();\r\n#endif\r\n");
             
-            #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 136 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 			GenerateRequestChecksumHandling(this.Operation, "snippet");
 
@@ -309,7 +309,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\t\r\n\r\n");
             
-            #line 136 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 140 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 	}
 	else if (payload?.Shape.IsString == true)
@@ -320,14 +320,14 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.Content = System.Text.Encoding.UTF8.GetBytes(publicRequest.");
             
-            #line 141 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.PropertyName));
             
             #line default
             #line hidden
             this.Write(");\r\n");
             
-            #line 142 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 146 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 	}
     else if (payload?.IsMemoryStream == true)
@@ -338,14 +338,14 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.ContentStream =  publicRequest.");
             
-            #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 151 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.PropertyName));
             
             #line default
             #line hidden
             this.Write(" ?? new MemoryStream();\r\n");
             
-            #line 148 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 152 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 		
 		var requiresLength = payload.RequiresLength;
 		if (!requiresLength && payload.Shape.IsStreaming && this.Operation.AuthType == OperationAuthType.V4UnsignedBody)
@@ -366,7 +366,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
 			}
 ");
             
-            #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 167 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 		else
@@ -381,7 +381,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
                     "onException(\"Cannot determine stream length for the payload when content-length " +
                     "is required.\");\r\n\t\t\t}\r\n");
             
-            #line 174 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 178 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 			}
 
@@ -393,7 +393,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
                     "ader] =\r\n\t\t\t\trequest.ContentStream.Length.ToString(CultureInfo.InvariantCulture)" +
                     ";\r\n");
             
-            #line 183 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 187 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 		}
 
@@ -403,7 +403,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             this.Write("\t\t\trequest.Headers[Amazon.Util.HeaderKeys.ContentTypeHeader] = \"application/octet" +
                     "-stream\";\r\n");
             
-            #line 187 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 191 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
     }
 	else if (payload?.Shape.IsPrimitiveType == true)
@@ -423,7 +423,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             this.Write("\t\t\tvar content = \"{}\";\r\n            request.Content = System.Text.Encoding.UTF8.G" +
                     "etBytes(content);\r\n");
             
-            #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 206 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 				GenerateRequestChecksumHandling(this.Operation, "content");
 
@@ -431,7 +431,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line default
             #line hidden
             
-            #line 205 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 209 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 
 	}
 
@@ -460,7 +460,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\t\t\trequest.UseQueryString = true;\r\n");
             
-            #line 218 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 222 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 	}
 
 	// We skip endpoint host prefix handling for S3 and S3 Control as it's implemented by endpoint rules.
@@ -474,7 +474,7 @@ public IRequest Marshall(AmazonWebServiceRequest input)
             #line hidden
             this.Write("\r\n\t\t\treturn request;\r\n\t\t}\r\n");
             
-            #line 229 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
+            #line 233 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCRequestMarshaller.tt"
 				
 		this.AddRequestSingletonMethod();
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.tt
index f90fe691939c..2383fd36653f 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCRequestMarshaller.tt
@@ -10,6 +10,9 @@
 #>
 using System.Text.Json;
 using System.Buffers;
+#if !NETFRAMEWORK
+using ThirdParty.RuntimeBackports;
+#endif
 #pragma warning disable CS0612,CS0618
 namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 {
@@ -93,9 +96,9 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 	if (this.Operation.RequestHasBodyMembers || shouldMarshallPayload)
 	{
 #>
-#if NETCOREAPP3_1_OR_GREATER
-			ArrayBufferWriter<byte> arrayBufferWriter = new ArrayBufferWriter<byte>();
-			using Utf8JsonWriter writer = new Utf8JsonWriter(arrayBufferWriter);
+#if !NETFRAMEWORK
+			using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+			using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
 #else
             using var memoryStream = new MemoryStream();
 			using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
@@ -124,8 +127,9 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 <#
 		}
 #>
-#if NETCOREAPP3_1_OR_GREATER
-            request.Content = arrayBufferWriter.WrittenMemory.ToArray();
+			// ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+			request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
 #else
 			request.Content = memoryStream.ToArray();
 #endif
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.cs
index 053f57ad0c6c..6749cdb7781c 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.cs
@@ -38,8 +38,8 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("using ThirdParty.Json.LitJson;\r\n\r\n#pragma warning disable CS0612,CS0618\r\nnamespac" +
-                    "e ");
+            this.Write("using System.Text.Json;\r\nusing Amazon.Util;\r\n#pragma warning disable CS0612,CS061" +
+                    "8\r\nnamespace ");
             
             #line 14 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
@@ -84,9 +84,9 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             
             #line default
             #line hidden
-            this.Write("Response();\r\n\r\n");
+            this.Write("Response();\r\n");
             
-            #line 30 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 29 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
     var payload = this.Operation.ResponsePayloadMember;
     var unmarshallPayload = payload != null && payload.IsStructure;
@@ -114,21 +114,21 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             #line hidden
             this.Write("            response.");
             
-            #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = new ");
             
-            #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.Shape.Name));
             
             #line default
             #line hidden
             this.Write("(context.Stream);\r\n");
             
-            #line 53 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
         }
         else if (payloadIsStream)
@@ -141,14 +141,14 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             #line hidden
             this.Write("            response.");
             
-            #line 60 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 59 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = context.Stream;\r\n");
             
-            #line 61 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 60 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             }
             else if (payload.ModelShape.IsString)
@@ -160,14 +160,14 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             this.Write("            using (var sr = new StreamReader(context.Stream))\r\n            {\r\n   " +
                     "             response.");
             
-            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = sr.ReadToEnd();\r\n            }\r\n");
             
-            #line 70 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 69 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             }
             else if (payload.ModelShape.IsMemoryStream)
@@ -180,14 +180,14 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
                     "yStream(context.Stream, ms);\r\n            ms.Seek(0, SeekOrigin.Begin);\r\n       " +
                     "     if (ms.Length > 0)\r\n                response.");
             
-            #line 79 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 78 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = ms;\r\n");
             
-            #line 80 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 79 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             }
             else
@@ -205,7 +205,8 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             
             #line default
             #line hidden
-            this.Write("            var unmarshaller = ");
+            this.Write("            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context." +
+                    "Stream);\r\n            var unmarshaller = ");
             
             #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(payload.DetermineTypeUnmarshallerInstantiate()));
@@ -219,7 +220,7 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             
             #line default
             #line hidden
-            this.Write(" = unmarshaller.Unmarshall(context);\r\n");
+            this.Write(" = unmarshaller.Unmarshall(context, ref reader);\r\n");
             
             #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
@@ -244,7 +245,7 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             
             #line default
             #line hidden
-            this.Write("Unmarshaller.Instance.Unmarshall(context);\r\n");
+            this.Write("Unmarshaller.Instance.Unmarshall(context, ref reader);\r\n");
             
             #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
@@ -255,10 +256,14 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             
             #line default
             #line hidden
-            this.Write("            context.Read();\r\n            int targetDepth = context.CurrentDepth;\r" +
-                    "\n            while (context.ReadAtDepth(targetDepth))\r\n            {\r\n");
+            this.Write(@"            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
+            int targetDepth = context.CurrentDepth;
+            while (context.ReadAtDepth(targetDepth, ref reader))
+            {
+");
             
-            #line 111 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 112 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
         
             foreach (var member in this.Operation.ResponseBodyMembers)
@@ -269,29 +274,29 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             #line hidden
             this.Write("                if (context.TestExpression(\"");
             
-            #line 116 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 117 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
             
             #line default
             #line hidden
             this.Write("\", targetDepth))\r\n                {\r\n                    var unmarshaller = ");
             
-            #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 119 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(";\r\n                    response.");
             
-            #line 119 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
-            this.Write(" = unmarshaller.Unmarshall(context);\r\n                    continue;\r\n            " +
-                    "    }\r\n");
+            this.Write(" = unmarshaller.Unmarshall(context, ref reader);\r\n                    continue;\r\n" +
+                    "                }\r\n");
             
-            #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 123 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             }
 
@@ -300,7 +305,7 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
             #line hidden
             this.Write("            }\r\n");
             
-            #line 126 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 127 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
         }
     }
@@ -323,7 +328,8 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
@@ -332,7 +338,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             using (var streamCopy = new MemoryStream(responseBodyBytes))
 ");
             
-            #line 152 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 154 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             if  (this.Config.ServiceModel.IsAwsQueryCompatible)
             {
@@ -341,17 +347,19 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             #line default
             #line hidden
             
-            #line 156 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
  // Create a copy of context with headers in the response 
+
+
             
             #line default
             #line hidden
-            this.Write("\r\n            using (var contextCopy = new JsonUnmarshallerContext(streamCopy, tr" +
-                    "ue, context.ResponseData))\r\n");
+            this.Write("            using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true" +
+                    ", context.ResponseData))\r\n");
             
-            #line 159 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 162 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
-            }
+            }   
             else
             {
 
@@ -361,16 +369,18 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             this.Write("            using (var contextCopy = new JsonUnmarshallerContext(streamCopy, fals" +
                     "e, null))\r\n");
             
-            #line 165 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 168 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
+            // Create a new reader because the stream has been read already in the original context
             }
 
             
             #line default
             #line hidden
-            this.Write("            {\r\n");
+            this.Write("            {\r\n                StreamingUtf8JsonReader readerCopy = new Streaming" +
+                    "Utf8JsonReader(streamCopy);\r\n");
             
-            #line 169 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 174 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
     foreach (var exception in this.Operation.Exceptions)
     {
@@ -380,22 +390,22 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             #line hidden
             this.Write("                if (errorResponse.Code != null && errorResponse.Code.Equals(\"");
             
-            #line 173 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 178 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(exception.Code));
             
             #line default
             #line hidden
             this.Write("\"))\r\n                {\r\n                    return ");
             
-            #line 175 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 180 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(exception.Name));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller.Instance.Unmarshall(contextCopy, errorResponse);\r\n                }\r" +
-                    "\n");
+            this.Write("Unmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);\r\n  " +
+                    "              }\r\n");
             
-            #line 177 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
     }
 
@@ -404,7 +414,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             #line hidden
             this.Write("            }\r\n");
             
-            #line 181 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 186 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             if  (this.Config.ServiceModel.IsAwsQueryCompatible)
             {
@@ -415,7 +425,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             #line hidden
             this.Write("            return new ");
             
-            #line 186 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 191 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.BaseException));
             
             #line default
@@ -423,7 +433,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             this.Write("(errorResponse.Message, errorResponse.InnerException, errorType, errorCode, error" +
                     "Response.RequestId, errorResponse.StatusCode);\r\n");
             
-            #line 187 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 192 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             }
             else
@@ -434,7 +444,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             #line hidden
             this.Write("            return new ");
             
-            #line 192 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 197 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.BaseException));
             
             #line default
@@ -442,7 +452,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             this.Write("(errorResponse.Message, errorResponse.InnerException, errorResponse.Type, errorRe" +
                     "sponse.Code, errorResponse.RequestId, errorResponse.StatusCode);\r\n");
             
-            #line 193 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 198 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
             }
 
@@ -451,7 +461,7 @@ public override AmazonServiceException UnmarshallException(JsonUnmarshallerConte
             #line hidden
             this.Write("        }\r\n\r\n");
             
-            #line 198 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 203 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
     if (payload != null && payload.Shape.IsStreaming)
     {
@@ -472,7 +482,7 @@ public override bool HasStreamingProperty
 
 ");
             
-            #line 213 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 218 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
 	}
     this.AddResponseSingletonMethod();
@@ -481,7 +491,7 @@ public override bool HasStreamingProperty
             #line default
             #line hidden
             
-            #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 222 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
     if(isEventStreamOutput)
     {
@@ -505,7 +515,7 @@ protected override bool ShouldReadEntireResponse(IWebResponseData response, bool
         public override bool HasStreamingProperty => true;
 ");
             
-            #line 235 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
+            #line 240 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCResponseUnmarshaller.tt"
 
     }
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.tt
index e2e75b05f40c..f26f178159f2 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCResponseUnmarshaller.tt
@@ -8,8 +8,8 @@
 
     AddCommonUsingStatements();
 #>
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 {
@@ -26,7 +26,6 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             <#=this.UnmarshallerBaseName #>Response response = new <#=this.Operation.Name #>Response();
-
 <#
     var payload = this.Operation.ResponsePayloadMember;
     var unmarshallPayload = payload != null && payload.IsStructure;
@@ -91,22 +90,24 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         else if (unmarshallPayload)
         {
 #>
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
             var unmarshaller = <#= payload.DetermineTypeUnmarshallerInstantiate() #>;
-            response.<#=payload.PropertyName#> = unmarshaller.Unmarshall(context);
+            response.<#=payload.PropertyName#> = unmarshaller.Unmarshall(context, ref reader);
 <#
         }
 		else if (this.IsWrapped)
 		{
 #>
-			response.<#=this.WrappedResultMember#> = <#=this.Structure.Name#>Unmarshaller.Instance.Unmarshall(context);
+			response.<#=this.WrappedResultMember#> = <#=this.Structure.Name#>Unmarshaller.Instance.Unmarshall(context, ref reader);
 <#
 		}
         else
         {
 #>
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
 <#
         
@@ -116,7 +117,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
                 if (context.TestExpression("<#=member.MarshallName#>", targetDepth))
                 {
                     var unmarshaller = <#= member.DetermineTypeUnmarshallerInstantiate() #>;
-                    response.<#=member.PropertyName#> = unmarshaller.Unmarshall(context);
+                    response.<#=member.PropertyName#> = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
 <#
@@ -142,7 +143,8 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
@@ -153,26 +155,29 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
             if  (this.Config.ServiceModel.IsAwsQueryCompatible)
             {
 #>
-<# // Create a copy of context with headers in the response #>
+<# // Create a copy of context with headers in the response 
 
+#>
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
 <#
-            }
+            }   
             else
             {
 #>
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, false, null))
 <#
+            // Create a new reader because the stream has been read already in the original context
             }
 #>
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
 <#
     foreach (var exception in this.Operation.Exceptions)
     {
 #>
                 if (errorResponse.Code != null && errorResponse.Code.Equals("<#=exception.Code #>"))
                 {
-                    return <#=exception.Name#>Unmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return <#=exception.Name#>Unmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
 <#
     }
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.cs
index 6efe94572797..c9c3f1b2b5d8 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.cs
@@ -38,31 +38,30 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("using ThirdParty.Json.LitJson;\r\n\r\n#pragma warning disable CS0612,CS0618\r\nnamespac" +
-                    "e ");
+            this.Write("#pragma warning disable CS0612,CS0618\r\nnamespace ");
             
-            #line 14 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 12 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
             #line hidden
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n\t/// <summary>\r\n\t/// ");
             
-            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 15 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write(" Marshaller\r\n\t/// </summary>\r\n\tpublic class ");
             
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write("Marshaller : IRequestMarshaller<");
             
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -77,7 +76,7 @@ public override string TransformText()
         /// <returns></returns>
 		public void Marshall(");
             
-            #line 27 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 25 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -85,7 +84,7 @@ public override string TransformText()
             this.Write(" requestObject, JsonMarshallerContext context)\r\n\t\t{\r\n\t\t\tif(requestObject == null)" +
                     "\r\n\t\t\t\treturn;\r\n");
             
-            #line 31 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 29 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
     ProcessMembers(0, "requestObject", this.Structure.Members);
 
@@ -95,14 +94,14 @@ public override string TransformText()
             this.Write("\t\t}\r\n\r\n        /// <summary>\r\n        /// Singleton Marshaller.\r\n        /// </su" +
                     "mmary>\r\n\t\tpublic readonly static ");
             
-            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 37 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write("Marshaller Instance = new ");
             
-            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+            #line 37 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -111,7 +110,7 @@ public override string TransformText()
             return this.GenerationEnvironment.ToString();
         }
         
-        #line 44 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 42 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 	protected void ProcessMembers(int level, string variableName, IEnumerable<Member> members)
 	{
@@ -122,91 +121,91 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            if(");
 
         
         #line default
         #line hidden
         
-        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(".IsSet");
 
         
         #line default
         #line hidden
         
-        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
 
         
         #line default
         #line hidden
         
-        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 48 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("())\r\n");
 
         
         #line default
         #line hidden
         
-        #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 49 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 49 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            {\r\n");
 
         
         #line default
         #line hidden
         
-        #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WritePropertyName(\"");
 
         
         #line default
         #line hidden
         
-        #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
 
         
         #line default
         #line hidden
         
-        #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 53 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			string memberProperty = variableName + "." + member.PropertyName + (member.IsNullable ? ".Value" : string.Empty);
 			if(member.IsStructure || member.IsList || member.IsMap)
@@ -221,7 +220,7 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 63 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 61 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
             }
 			else if(member.IsMemoryStream)
@@ -231,35 +230,35 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 66 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 66 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteStringValue(StringUtils.FromMemoryStream(");
 
         
         #line default
         #line hidden
         
-        #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 66 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName + "." + member.PropertyName));
 
         
         #line default
         #line hidden
         
-        #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 66 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 69 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 			else
@@ -272,49 +271,49 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteStringValue(");
 
         
         #line default
         #line hidden
         
-        #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.PrimitiveMarshaller));
 
         
         #line default
         #line hidden
         
-        #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("(");
 
         
         #line default
         #line hidden
         
-        #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName + "." + member.PropertyName));
 
         
         #line default
         #line hidden
         
-        #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 78 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 76 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 				}
 				else if(member.Shape.IsDouble)
@@ -324,161 +323,161 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 81 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 81 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\tif(StringUtils.IsSpecialDoubleValue(");
 
         
         #line default
         #line hidden
         
-        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 81 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 81 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("))\r\n");
 
         
         #line default
         #line hidden
         
-        #line 84 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 82 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 84 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 82 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t{\r\n");
 
         
         #line default
         #line hidden
         
-        #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t\tcontext.Writer.WriteStringValue(StringUtils.FromSpecialDoubleValue(");
 
         
         #line default
         #line hidden
         
-        #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 86 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 84 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 86 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 84 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t}\r\n");
 
         
         #line default
         #line hidden
         
-        #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 85 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\telse\r\n");
 
         
         #line default
         #line hidden
         
-        #line 88 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 86 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 88 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 86 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t{\r\n");
 
         
         #line default
         #line hidden
         
-        #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t\tcontext.Writer.WriteNumberValue(");
 
         
         #line default
         #line hidden
         
-        #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 90 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 88 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 90 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 88 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t}\r\n");
 
         
         #line default
         #line hidden
         
-        #line 91 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 				}
 				else if(member.Shape.IsFloat)
@@ -488,161 +487,161 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\tif(StringUtils.IsSpecialFloatValue(");
 
         
         #line default
         #line hidden
         
-        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("))\r\n");
 
         
         #line default
         #line hidden
         
-        #line 97 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 95 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 97 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 95 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t{\r\n");
 
         
         #line default
         #line hidden
         
-        #line 98 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 98 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t\tcontext.Writer.WriteStringValue(StringUtils.FromSpecialFloatValue(");
 
         
         #line default
         #line hidden
         
-        #line 98 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 98 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 99 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 97 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 99 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 97 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t}\r\n");
 
         
         #line default
         #line hidden
         
-        #line 100 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 98 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 100 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 98 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\telse\r\n");
 
         
         #line default
         #line hidden
         
-        #line 101 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 99 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 101 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 99 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t{\r\n");
 
         
         #line default
         #line hidden
         
-        #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 100 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 100 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t\tcontext.Writer.WriteNumberValue(");
 
         
         #line default
         #line hidden
         
-        #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 100 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 100 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 103 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 101 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 103 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 101 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\t}\r\n");
 
         
         #line default
         #line hidden
         
-        #line 104 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 				}
 				else
@@ -653,7 +652,7 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 110 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 108 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 				}
 			}
@@ -662,21 +661,21 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 114 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 112 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 114 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 112 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            }\r\n\r\n");
 
         
         #line default
         #line hidden
         
-        #line 116 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 114 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			if(member.IsIdempotent)
 			{
@@ -685,119 +684,119 @@ protected void ProcessMembers(int level, string variableName, IEnumerable<Member
         #line default
         #line hidden
         
-        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(" \t\t   else if(!(");
 
         
         #line default
         #line hidden
         
-        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(".IsSet");
 
         
         #line default
         #line hidden
         
-        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
 
         
         #line default
         #line hidden
         
-        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 118 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("()))\r\n");
 
         
         #line default
         #line hidden
         
-        #line 121 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 119 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 121 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 119 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(" \t\t   {\r\n");
 
         
         #line default
         #line hidden
         
-        #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WritePropertyName(\"");
 
         
         #line default
         #line hidden
         
-        #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
 
         
         #line default
         #line hidden
         
-        #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 120 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 123 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 121 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 123 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 121 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteStringValue(Guid.NewGuid().ToString());\r\n");
 
         
         #line default
         #line hidden
         
-        #line 124 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 124 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(" \t\t   }\r\n");
 
         
         #line default
         #line hidden
         
-        #line 125 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 123 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 					
 			}
 		}
@@ -810,70 +809,70 @@ protected void ProcessRequestPayloadMember(int level, string variableName, Shape
         #line default
         #line hidden
         
-        #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 130 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\r\n");
 
         
         #line default
         #line hidden
         
-        #line 134 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 134 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                var marshaller = ");
 
         
         #line default
         #line hidden
         
-        #line 134 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(structure.Name));
 
         
         #line default
         #line hidden
         
-        #line 134 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("Marshaller.Instance;\r\n");
 
         
         #line default
         #line hidden
         
-        #line 135 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 133 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 135 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 133 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                marshaller.Marshall(");
 
         
         #line default
         #line hidden
         
-        #line 135 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 133 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 135 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 133 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(", context);\r\n");
 
         
         #line default
         #line hidden
         
-        #line 136 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 134 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
     }
 
@@ -888,77 +887,77 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 146 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 144 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 146 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 144 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteStartArray();\r\n");
 
         
         #line default
         #line hidden
         
-        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            foreach(var ");
 
         
         #line default
         #line hidden
         
-        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(flatVariableName));
 
         
         #line default
         #line hidden
         
-        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("ListValue in ");
 
         
         #line default
         #line hidden
         
-        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 145 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(")\r\n");
 
         
         #line default
         #line hidden
         
-        #line 148 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 146 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 148 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 146 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            {\r\n");
 
         
         #line default
         #line hidden
         
-        #line 149 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 147 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
  
 				ProcessStructure(level + 1, flatVariableName + "ListValue", structure.ListShape);
 
@@ -966,35 +965,35 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 152 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 150 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 152 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 150 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            }\r\n");
 
         
         #line default
         #line hidden
         
-        #line 153 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 151 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 153 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 151 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteEndArray();\r\n");
 
         
         #line default
         #line hidden
         
-        #line 154 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 152 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 			else if(structure.IsMap)
@@ -1004,147 +1003,147 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 159 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 157 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 159 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 157 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteStartObject();\r\n");
 
         
         #line default
         #line hidden
         
-        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            foreach (var ");
 
         
         #line default
         #line hidden
         
-        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(flatVariableName));
 
         
         #line default
         #line hidden
         
-        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("Kvp in ");
 
         
         #line default
         #line hidden
         
-        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 158 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(")\r\n");
 
         
         #line default
         #line hidden
         
-        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 159 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 159 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            {\r\n");
 
         
         #line default
         #line hidden
         
-        #line 162 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 162 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WritePropertyName(");
 
         
         #line default
         #line hidden
         
-        #line 162 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(flatVariableName));
 
         
         #line default
         #line hidden
         
-        #line 162 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 160 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("Kvp.Key);\r\n");
 
         
         #line default
         #line hidden
         
-        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                var ");
 
         
         #line default
         #line hidden
         
-        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(flatVariableName));
 
         
         #line default
         #line hidden
         
-        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("Value = ");
 
         
         #line default
         #line hidden
         
-        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(flatVariableName));
 
         
         #line default
         #line hidden
         
-        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 161 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("Kvp.Value;\r\n\r\n");
 
         
         #line default
         #line hidden
         
-        #line 165 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 163 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
  
 				ProcessStructure(level + 1, flatVariableName + "Value", structure.ValueShape);
 
@@ -1152,35 +1151,35 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 168 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 166 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 168 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 166 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            }\r\n");
 
         
         #line default
         #line hidden
         
-        #line 169 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 167 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 169 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 167 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteEndObject();\r\n");
 
         
         #line default
         #line hidden
         
-        #line 170 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 168 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 			else if(structure.IsDocument)
@@ -1190,14 +1189,14 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 175 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 173 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 175 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 173 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            Amazon.Runtime.Documents.Internal.Transform.DocumentMarshaller.Instan" +
         "ce.Write(context.Writer, ");
 
@@ -1205,21 +1204,21 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 175 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 173 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 175 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 173 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 176 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 174 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 
 			}
@@ -1230,91 +1229,91 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 180 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 180 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteStartObject();\r\n\r\n");
 
         
         #line default
         #line hidden
         
-        #line 184 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 184 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            var marshaller = ");
 
         
         #line default
         #line hidden
         
-        #line 184 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(structure.Name));
 
         
         #line default
         #line hidden
         
-        #line 184 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 182 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("Marshaller.Instance;\r\n");
 
         
         #line default
         #line hidden
         
-        #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 183 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 183 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            marshaller.Marshall(");
 
         
         #line default
         #line hidden
         
-        #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 183 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 183 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(", context);\r\n\r\n");
 
         
         #line default
         #line hidden
         
-        #line 187 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 187 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteEndObject();\r\n");
 
         
         #line default
         #line hidden
         
-        #line 188 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 186 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 			else if(structure.IsMemoryStream)
@@ -1324,35 +1323,35 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 193 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 191 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 193 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 191 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("            context.Writer.WriteStringValue(StringUtils.FromMemoryStream(");
 
         
         #line default
         #line hidden
         
-        #line 193 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 191 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 193 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 191 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 194 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 192 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 			else
@@ -1365,49 +1364,49 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 200 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 200 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("\t\t\t\tcontext.Writer.WriteStringValue(");
 
         
         #line default
         #line hidden
         
-        #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 200 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(structure.PrimitiveMarshaller(MarshallLocation.Body)));
 
         
         #line default
         #line hidden
         
-        #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 200 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("(");
 
         
         #line default
         #line hidden
         
-        #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 200 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(variableName));
 
         
         #line default
         #line hidden
         
-        #line 202 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 200 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 203 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 201 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 				}
 				else
@@ -1422,7 +1421,7 @@ protected void ProcessStructure(int level, string variableName, Shape structure)
         #line default
         #line hidden
         
-        #line 213 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 211 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 	protected void DetermineCustomMarshallerJsonWriteMethod(Member member, string memberProperty, int level)
 	{
@@ -1433,49 +1432,49 @@ protected void DetermineCustomMarshallerJsonWriteMethod(Member member, string me
         #line default
         #line hidden
         
-        #line 219 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 219 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteNumberValue(");
 
         
         #line default
         #line hidden
         
-        #line 219 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.CustomMarshallerTransformation));
 
         
         #line default
         #line hidden
         
-        #line 219 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("(");
 
         
         #line default
         #line hidden
         
-        #line 219 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 219 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 217 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 220 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 218 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 		}
 		else
@@ -1485,49 +1484,49 @@ protected void DetermineCustomMarshallerJsonWriteMethod(Member member, string me
         #line default
         #line hidden
         
-        #line 225 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 223 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 225 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 223 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteStringValue(");
 
         
         #line default
         #line hidden
         
-        #line 225 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 223 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(member.CustomMarshallerTransformation));
 
         
         #line default
         #line hidden
         
-        #line 225 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 223 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("(");
 
         
         #line default
         #line hidden
         
-        #line 225 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 223 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 225 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 223 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 226 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 224 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 		}	
 	}
@@ -1536,7 +1535,7 @@ protected void DetermineCustomMarshallerJsonWriteMethod(Member member, string me
         #line default
         #line hidden
         
-        #line 230 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 228 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 	/// https://smithy.io/2.0/aws/protocols/aws-restjson1-protocol.html#json-shape-serialization
 	/// timestamps in json protocols use unixtimestamp if none is specified (by default)
@@ -1552,35 +1551,35 @@ protected void DetermineNormalJsonWriteMethod(Shape shape, string memberProperty
         #line default
         #line hidden
         
-        #line 241 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 241 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteStringValue(");
 
         
         #line default
         #line hidden
         
-        #line 241 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 241 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 242 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 240 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 		}
 		else if (shape.IsDateTime)
@@ -1592,35 +1591,35 @@ protected void DetermineNormalJsonWriteMethod(Shape shape, string memberProperty
         #line default
         #line hidden
         
-        #line 249 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 247 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 249 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 247 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteStringValue(");
 
         
         #line default
         #line hidden
         
-        #line 249 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 247 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 249 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 247 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 250 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 248 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 			else
@@ -1630,14 +1629,14 @@ protected void DetermineNormalJsonWriteMethod(Shape shape, string memberProperty
         #line default
         #line hidden
         
-        #line 255 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 253 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 255 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 253 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteNumberValue(Convert.ToInt64(StringUtils.FromD" +
         "ateTimeToUnixTimestamp(");
 
@@ -1645,21 +1644,21 @@ protected void DetermineNormalJsonWriteMethod(Shape shape, string memberProperty
         #line default
         #line hidden
         
-        #line 255 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 253 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 255 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 253 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(")));\r\n");
 
         
         #line default
         #line hidden
         
-        #line 256 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 254 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 			}
 		}
@@ -1670,35 +1669,35 @@ protected void DetermineNormalJsonWriteMethod(Shape shape, string memberProperty
         #line default
         #line hidden
         
-        #line 262 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 260 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 262 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 260 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteNumberValue(");
 
         
         #line default
         #line hidden
         
-        #line 262 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 260 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 262 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 260 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 263 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 261 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 		}
 		else if (shape.IsBoolean)
@@ -1708,35 +1707,35 @@ protected void DetermineNormalJsonWriteMethod(Shape shape, string memberProperty
         #line default
         #line hidden
         
-        #line 268 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 266 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(new string(' ', level * 4)));
 
         
         #line default
         #line hidden
         
-        #line 268 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 266 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write("                context.Writer.WriteBooleanValue(");
 
         
         #line default
         #line hidden
         
-        #line 268 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 266 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(this.ToStringHelper.ToStringWithCulture(memberProperty));
 
         
         #line default
         #line hidden
         
-        #line 268 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 266 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 this.Write(");\r\n");
 
         
         #line default
         #line hidden
         
-        #line 269 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
+        #line 267 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureMarshaller.tt"
 
 		}
 		else
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.tt
index c509b70ac9e1..1151087e43c7 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureMarshaller.tt
@@ -8,8 +8,6 @@
 
 	AddCommonUsingStatements();
 #>
-using ThirdParty.Json.LitJson;
-
 #pragma warning disable CS0612,CS0618
 namespace <#=        this.Config.Namespace #>.Model.Internal.MarshallTransformations
 {
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.cs
index 770b04b9de17..975db418ad89 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.cs
@@ -38,10 +38,9 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("using ThirdParty.Json.LitJson;\r\n\r\n#pragma warning disable CS0612,CS0618\r\nnamespac" +
-                    "e ");
+            this.Write("using System.Text.Json;\r\n#pragma warning disable CS0612,CS0618\r\nnamespace ");
             
-            #line 14 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 13 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
@@ -49,83 +48,58 @@ public override string TransformText()
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n    /// <summary>\r\n    /// Response U" +
                     "nmarshaller for ");
             
-            #line 17 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 16 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" Object\r\n    /// </summary>  \r\n    public class ");
             
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 18 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller : IUnmarshaller<");
+            this.Write("Unmarshaller : IJsonUnmarshaller<");
             
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 18 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write(", XmlUnmarshallerContext>, IUnmarshaller<");
-            
-            #line 19 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(", JsonUnmarshallerContext>\r\n    {\r\n        /// <summary>\r\n        /// Unmarshalle" +
-                    "r the response from the service to the response class.\r\n        /// </summary>  " +
-                    "\r\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n " +
-                    "       ");
-            
-            #line 26 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(" IUnmarshaller<");
-            
-            #line 26 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(@", XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
+            this.Write(@", JsonUnmarshallerContext>
+    {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name=""context""></param>
+        /// <param name=""reader""></param>
         /// <returns>The unmarshalled object</returns>
         public ");
             
-            #line 36 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 26 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write(" Unmarshall(JsonUnmarshallerContext context)\r\n        {\r\n            ");
+            this.Write(" Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)\r" +
+                    "\n        {\r\n            ");
             
-            #line 38 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 28 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" unmarshalledObject = new ");
             
-            #line 38 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 28 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write("();\r\n            if (context.IsEmptyResponse)\r\n                return null;\r\n");
             
-            #line 41 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 31 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     //HasImplicitEventPayloadMembers means that the structure does not have a member with the EventPayload trait
     if(this.Structure != null && this.Structure.IsEvent && !this.Structure.HasImplicitEventPayloadMembers())
@@ -140,14 +114,14 @@ public override string TransformText()
             this.Write("            using (var sr = new StreamReader(context.Stream))\r\n            {\r\n   " +
                     "             unmarshalledObject.");
             
-            #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 41 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(eventPayloadMember.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = sr.ReadToEnd();\r\n            }\r\n");
             
-            #line 53 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 43 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
         }
 
@@ -155,7 +129,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 56 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 46 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
         else
         {
@@ -165,14 +139,14 @@ public override string TransformText()
             #line hidden
             this.Write("            unmarshalledObject.");
             
-            #line 60 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 50 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(eventPayloadMember.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = context.Stream as MemoryStream;\r\n");
             
-            #line 61 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 51 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
         }
 
@@ -180,7 +154,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 64 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 54 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     }
 
@@ -188,7 +162,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     if(this.Structure != null && (this.Structure.HasImplicitEventPayloadMembers() || !this.Structure.IsEvent))
     {
@@ -196,12 +170,16 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("            context.Read();\r\n            if (context.CurrentTokenType == JsonToke" +
-                    "n.Null) \r\n                return null;\r\n\r\n            int targetDepth = context." +
-                    "CurrentDepth;\r\n            while (context.ReadAtDepth(targetDepth))\r\n           " +
-                    " {\r\n");
+            this.Write(@"            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
+                return null;
+
+            int targetDepth = context.CurrentDepth;
+            while (context.ReadAtDepth(targetDepth, ref reader))
+            {
+");
             
-            #line 78 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     }
 
@@ -209,7 +187,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 81 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 71 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     if(this.Structure != null && (!this.Structure.IsEvent ||  this.Structure.HasImplicitEventPayloadMembers()))
     {
@@ -221,29 +199,29 @@ public override string TransformText()
             #line hidden
             this.Write("                if (context.TestExpression(\"");
             
-            #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 77 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
             
             #line default
             #line hidden
             this.Write("\", targetDepth))\r\n                {\r\n                    var unmarshaller = ");
             
-            #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 79 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(";\r\n                    unmarshalledObject.");
             
-            #line 90 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 80 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
-            this.Write(" = unmarshaller.Unmarshall(context);\r\n                    continue;\r\n            " +
-                    "    }\r\n");
+            this.Write(" = unmarshaller.Unmarshall(context, ref reader);\r\n                    continue;\r\n" +
+                    "                }\r\n");
             
-            #line 93 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 83 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
         }
     }
@@ -252,7 +230,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 97 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 87 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     if(this.Structure != null && (!this.Structure.IsEvent || this.Structure.HasImplicitEventPayloadMembers()))
     {
@@ -262,7 +240,7 @@ public override string TransformText()
             #line hidden
             this.Write("            }\r\n");
             
-            #line 102 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 92 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     }
 
@@ -271,7 +249,7 @@ public override string TransformText()
             #line hidden
             this.Write("            return unmarshalledObject;\r\n        }\r\n\r\n\r\n");
             
-            #line 109 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
+            #line 99 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\JsonRPCStructureUnmarshaller.tt"
 
     this.AddStructureSingletonMethod();
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.tt
index 87a63ddc1437..f46be03f43a3 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/JsonRPCStructureUnmarshaller.tt
@@ -8,32 +8,22 @@
 
     AddCommonUsingStatements();
 #>
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for <#=this.UnmarshallerBaseName #> Object
     /// </summary>  
-    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>, IUnmarshaller<<#=this.UnmarshallerBaseName #>, JsonUnmarshallerContext>
+    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IJsonUnmarshaller<<#=this.UnmarshallerBaseName #>, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        <#=this.UnmarshallerBaseName #> IUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context)
+        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             <#=this.UnmarshallerBaseName #> unmarshalledObject = new <#=this.UnmarshallerBaseName #>();
             if (context.IsEmptyResponse)
@@ -68,12 +58,12 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
     if(this.Structure != null && (this.Structure.HasImplicitEventPayloadMembers() || !this.Structure.IsEvent))
     {
 #>
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
 <#
     }
@@ -87,7 +77,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
                 if (context.TestExpression("<#=member.MarshallName#>", targetDepth))
                 {
                     var unmarshaller = <#= member.DetermineTypeUnmarshallerInstantiate() #>;
-                    unmarshalledObject.<#=member.PropertyName#> = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.<#=member.PropertyName#> = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
 <#
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.cs
index 7f4188e6d184..516fcc2b4f42 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.cs
@@ -18,7 +18,7 @@ namespace ServiceClientGenerator.Generators.Marshallers
     /// Class to produce the template output
     /// </summary>
     
-    #line 1 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+    #line 1 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "17.0.0.0")]
     public partial class RestXmlExceptionUnmarshaller : BaseResponseUnmarshaller
     {
@@ -29,7 +29,7 @@ public partial class RestXmlExceptionUnmarshaller : BaseResponseUnmarshaller
         public override string TransformText()
         {
             
-            #line 6 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 6 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
 
     AddLicenseHeader();
 
@@ -40,7 +40,7 @@ public override string TransformText()
             #line hidden
             this.Write("\r\n#pragma warning disable CS0612,CS0618\r\nnamespace ");
             
-            #line 13 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 13 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
@@ -48,21 +48,21 @@ public override string TransformText()
             this.Write(".Model.Internal.MarshallTransformations\r\n{\r\n    /// <summary>\r\n    /// Response U" +
                     "nmarshaller for ");
             
-            #line 16 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 16 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" operation\r\n    /// </summary>  \r\n    public class ");
             
-            #line 18 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 18 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller : IErrorResponseUnmarshaller<");
+            this.Write("Unmarshaller : IXmlErrorResponseUnmarshaller<");
             
-            #line 18 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 18 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -72,7 +72,7 @@ public override string TransformText()
                     "\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n  " +
                     "      public ");
             
-            #line 25 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 25 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -90,7 +90,7 @@ public override string TransformText()
         /// <returns></returns>
         public ");
             
-            #line 36 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 36 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -98,14 +98,14 @@ public override string TransformText()
             this.Write(" Unmarshall(XmlUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse" +
                     " errorResponse)\r\n        {\r\n            ");
             
-            #line 38 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 38 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
             this.Write(" response = new ");
             
-            #line 38 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 38 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
@@ -119,7 +119,7 @@ public override string TransformText()
                 {
 ");
             
-            #line 45 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 45 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
     
     foreach (var member in this.Structure.Members)
     {
@@ -132,56 +132,56 @@ public override string TransformText()
             #line hidden
             this.Write("                    if (context.TestExpression(\"");
             
-            #line 52 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
             
             #line default
             #line hidden
             this.Write("/");
             
-            #line 52 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 52 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(listMarshallName));
             
             #line default
             #line hidden
             this.Write("\"))\r\n                    {\r\n                        var unmarshaller = ");
             
-            #line 54 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 54 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(";\r\n                        if (response.");
             
-            #line 55 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 55 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(" == null)\r\n                        {\r\n                            response.");
             
-            #line 57 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = new ");
             
-            #line 57 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
             #line hidden
             this.Write("();\r\n                        }\r\n                        response.");
             
-            #line 59 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 59 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(".Add(unmarshaller.Unmarshall(context));\r\n                    }\r\n");
             
-            #line 61 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 61 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
 
         }
         else
@@ -192,28 +192,28 @@ public override string TransformText()
             #line hidden
             this.Write("                    if (context.TestExpression(\"");
             
-            #line 66 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 66 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.MarshallName));
             
             #line default
             #line hidden
             this.Write("\"))\r\n                    {\r\n                        var unmarshaller = ");
             
-            #line 68 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineTypeUnmarshallerInstantiate()));
             
             #line default
             #line hidden
             this.Write(";\r\n                        response.");
             
-            #line 69 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 69 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(" = unmarshaller.Unmarshall(context);\r\n                    }\r\n");
             
-            #line 71 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 71 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
 
         }
     }
@@ -223,7 +223,7 @@ public override string TransformText()
             #line hidden
             this.Write("                }\r\n            }\r\n            return response;\r\n        }\r\n\r\n");
             
-            #line 80 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
+            #line 80 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlExceptionUnmarshaller.tt"
 
     this.AddStructureSingletonMethod();
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.tt
index 07d55b10dca8..6c8ce78f5466 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlExceptionUnmarshaller.tt
@@ -15,7 +15,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for <#=this.UnmarshallerBaseName #> operation
     /// </summary>  
-    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IErrorResponseUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>
+    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IXmlErrorResponseUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.cs
index 9fb648ede0a3..74ab4807fd95 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.cs
@@ -581,7 +581,7 @@ public override AmazonWebServiceResponse Unmarshall(XmlUnmarshallerContext conte
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            ErrorResponse errorResponse = ErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.tt
index e473947324a2..a5b3af7512b1 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlResponseUnmarshaller.tt
@@ -246,7 +246,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            ErrorResponse errorResponse = ErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.cs b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.cs
index 42e69ac2f4d0..edb58da33d98 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.cs
@@ -60,24 +60,17 @@ public override string TransformText()
             
             #line default
             #line hidden
-            this.Write("Unmarshaller : IUnmarshaller<");
+            this.Write("Unmarshaller : IXmlUnmarshaller<");
             
             #line 18 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
             
             #line default
             #line hidden
-            this.Write(", XmlUnmarshallerContext>, IUnmarshaller<");
-            
-            #line 18 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(", JsonUnmarshallerContext>\r\n    {\r\n        /// <summary>\r\n        /// Unmarshalle" +
-                    "r the response from the service to the response class.\r\n        /// </summary>  " +
-                    "\r\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n " +
-                    "       public ");
+            this.Write(", XmlUnmarshallerContext>\r\n    {\r\n        /// <summary>\r\n        /// Unmarshaller" +
+                    " the response from the service to the response class.\r\n        /// </summary>  \r" +
+                    "\n        /// <param name=\"context\"></param>\r\n        /// <returns></returns>\r\n  " +
+                    "      public ");
             
             #line 25 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlStructureUnmarshaller.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
@@ -321,23 +314,9 @@ public override string TransformText()
             }          
             return unmarshalledObject;
         }
-        
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name=""context""></param>
-        /// <returns></returns>
-        public ");
-            
-            #line 128 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlStructureUnmarshaller.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(this.UnmarshallerBaseName));
-            
-            #line default
-            #line hidden
-            this.Write(" Unmarshall(JsonUnmarshallerContext context)\r\n        {\r\n            throw new No" +
-                    "tImplementedException();\r\n        }\r\n\r\n");
+");
             
-            #line 133 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlStructureUnmarshaller.tt"
+            #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\Marshallers\RestXmlStructureUnmarshaller.tt"
 
     this.AddStructureSingletonMethod();
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.tt b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.tt
index 4dd4fe8f796f..1cc56dbbf1de 100644
--- a/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/Marshallers/RestXmlStructureUnmarshaller.tt
@@ -15,7 +15,7 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for <#=this.UnmarshallerBaseName #> Object
     /// </summary>  
-    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>, IUnmarshaller<<#=this.UnmarshallerBaseName #>, JsonUnmarshallerContext>
+    public class <#=this.UnmarshallerBaseName #>Unmarshaller : IXmlUnmarshaller<<#=this.UnmarshallerBaseName #>, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
@@ -119,17 +119,6 @@ namespace <#=this.Config.Namespace #>.Model.Internal.MarshallTransformations
             }          
             return unmarshalledObject;
         }
-        
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
-        /// <returns></returns>
-        public <#=this.UnmarshallerBaseName #> Unmarshall(JsonUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
 <#
     this.AddStructureSingletonMethod();
 #>
diff --git a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.cs b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.cs
index ecc5b4f08fee..60f64abc0828 100644
--- a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.cs
@@ -18,7 +18,7 @@ namespace ServiceClientGenerator.Generators.SourceFiles
     /// Class to produce the template output
     /// </summary>
     
-    #line 1 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+    #line 1 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.TextTemplating", "17.0.0.0")]
     public partial class EventStreamGenerator : StructureGenerator
     {
@@ -29,7 +29,7 @@ public partial class EventStreamGenerator : StructureGenerator
         public override string TransformText()
         {
             
-            #line 6 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 6 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
     bool isRequest = this.Operation.RequestStructure.Members.Any(x => x.ModelShape.MarshallName == this.Structure.Name);
     bool isResponse = this.Operation.ResponseStructure.Members.Any(x => x.ModelShape.MarshallName == this.Structure.Name);
@@ -40,7 +40,7 @@ public override string TransformText()
             this.Write("    [System.Diagnostics.CodeAnalysis.SuppressMessage(\"Naming\", \"CA1710:Identifier" +
                     "s should have correct suffix\", Justification = \"");
             
-            #line 10 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 10 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -49,14 +49,14 @@ public override string TransformText()
     [System.Diagnostics.CodeAnalysis.SuppressMessage(""Microsoft.Design"", ""CA1063"", Justification = ""IDisposable is a transient interface from IEventStream. Users need to be able to call Dispose."")]
     public sealed class ");
             
-            #line 12 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 12 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write(" : EnumerableEventStream<IEventStreamEvent, ");
             
-            #line 12 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 12 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ClassName));
             
             #line default
@@ -71,7 +71,7 @@ public sealed class ");
         {
 ");
             
-            #line 20 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 20 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         string protocol = null;
         if (string.Equals(this.Config.ServiceModel.Protocol,"rest-json", StringComparison.OrdinalIgnoreCase) || string.Equals(this.Config.ServiceModel.Protocol,"json", StringComparison.OrdinalIgnoreCase))
@@ -87,7 +87,7 @@ public sealed class ");
             #line default
             #line hidden
             
-            #line 31 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 31 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         if(isResponse)
         {
@@ -98,7 +98,7 @@ public sealed class ");
             this.Write("            {\"Initial-Response\", payload => new InitialResponseEvent(payload)},\r\n" +
                     "");
             
-            #line 36 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 36 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         }
 
@@ -106,7 +106,7 @@ public sealed class ");
             #line default
             #line hidden
             
-            #line 39 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         else if(isRequest)
         {
@@ -116,7 +116,7 @@ public sealed class ");
             #line hidden
             this.Write("            {\"Initial-Request\", payload => new InitialRequestEvent(payload)},\r\n");
             
-            #line 44 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 44 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         }
 
@@ -124,41 +124,76 @@ public sealed class ");
             #line default
             #line hidden
             
-            #line 47 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 47 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         foreach(var member in this.Structure.Members)
         {
-        if(member.ModelShape.IsEvent)
+            if(member.ModelShape.IsEvent)
             {
+                if (protocol == "Json")
+                {
 
             
             #line default
             #line hidden
             this.Write("            {\"");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 55 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
-            this.Write("\", payload => new ");
+            this.Write("\", payload => \r\n                {\r\n                    var context = EventStreamU" +
+                    "tils.ConvertMessageTo");
+            
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(protocol));
+            
+            #line default
+            #line hidden
+            this.Write("Context(payload);\r\n                    var reader = new StreamingUtf8JsonReader(c" +
+                    "ontext.Stream);\r\n                    return new ");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 59 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
             #line hidden
-            this.Write("Unmarshaller().Unmarshall(EventStreamUtils.ConvertMessageTo");
+            this.Write("Unmarshaller().Unmarshall(context, ref reader);\r\n                }\r\n            }" +
+                    ",\r\n");
             
-            #line 53 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
-            this.Write(this.ToStringHelper.ToStringWithCulture(protocol));
+            #line 62 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+
+                }
+                else if (protocol == "Xml")
+                {
+
+            
+            #line default
+            #line hidden
+            this.Write("            {\"");
+            
+            #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
-            this.Write("Context(payload))},\r\n");
+            this.Write("\", payload => new ");
+            
+            #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
-            #line 54 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line default
+            #line hidden
+            this.Write("Unmarshaller().Unmarshall(context);},\r\n");
+            
+            #line 68 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
+                }
+                else
+                {
+                    throw new NotImplementedException("The given protocol is not supported");
+                }
             }
         }
 
@@ -170,7 +205,7 @@ public sealed class ");
                     "</summary>\r\n        protected override IDictionary<string,Func<IEventStreamMessa" +
                     "ge,");
             
-            #line 62 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 81 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ClassName));
             
             #line default
@@ -178,55 +213,102 @@ public sealed class ");
             this.Write("EventStreamException>> ExceptionMapping {get;} =\r\n        new Dictionary<string,F" +
                     "unc<IEventStreamMessage,");
             
-            #line 63 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 82 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ClassName));
             
             #line default
             #line hidden
             this.Write("EventStreamException>>(StringComparer.OrdinalIgnoreCase)\r\n        {\r\n");
             
-            #line 65 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 84 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         foreach(var member in this.Structure.Members)
         {
             if(member.ModelShape.IsException)
             {
+                if (protocol == "Json")
+                {
+
+            
+            #line default
+            #line hidden
+            this.Write("                    {\"");
+            
+            #line 92 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write("\", payload => \r\n                        {\r\n                            var contex" +
+                    "t = EventStreamUtils.ConvertMessageTo");
+            
+            #line 94 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(protocol));
+            
+            #line default
+            #line hidden
+            this.Write("Context(payload);\r\n                            var reader = new StreamingUtf8Json" +
+                    "Reader(context.Stream);\r\n                            return new ");
+            
+            #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ClassName));
+            
+            #line default
+            #line hidden
+            this.Write("EventStreamException(Encoding.UTF8.GetString(payload.Payload), new ");
+            
+            #line 96 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.ModelShape));
+            
+            #line default
+            #line hidden
+            this.Write("Unmarshaller().Unmarshall(context, ref reader));\r\n                        }\r\n    " +
+                    "                },\r\n");
+            
+            #line 99 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+
+                }
+                else if (protocol == "Xml")
+                {
 
             
             #line default
             #line hidden
             this.Write("            { \"");
             
-            #line 71 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 104 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write("\", payload => new ");
             
-            #line 71 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 104 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ClassName));
             
             #line default
             #line hidden
             this.Write("EventStreamException(Encoding.UTF8.GetString(payload.Payload), new ");
             
-            #line 71 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 104 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.ModelShape));
             
             #line default
             #line hidden
             this.Write("Unmarshaller().Unmarshall(EventStreamUtils.ConvertMessageTo");
             
-            #line 71 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 104 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(protocol));
             
             #line default
             #line hidden
             this.Write("Context(payload))) },\r\n");
             
-            #line 72 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 105 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
+                }
+                else
+                    throw new NotImplementedException("The given protocol is not supported");
             }
         }
 
@@ -257,14 +339,14 @@ protected override bool IsProcessing
         /// </summary>
         public override event EventHandler<EventStreamExceptionReceivedArgs<");
             
-            #line 98 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 134 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.ClassName));
             
             #line default
             #line hidden
             this.Write("EventStreamException>> ExceptionReceived;\r\n");
             
-            #line 99 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 135 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         if(isResponse)
         {
@@ -276,7 +358,7 @@ protected override bool IsProcessing
                     "/summary>\r\n        public event EventHandler<EventStreamEventReceivedArgs<Initia" +
                     "lResponseEvent>> InitialResponseReceived;\r\n");
             
-            #line 107 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 143 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         }
         else if(isRequest)
@@ -289,7 +371,7 @@ protected override bool IsProcessing
                     "summary>\r\n        public event EventHandler<EventStreamEventReceivedArgs<Initial" +
                     "RequestEvent>> InitialRequestReceived;\r\n");
             
-            #line 116 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 152 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         }
 
@@ -297,7 +379,7 @@ protected override bool IsProcessing
             #line default
             #line hidden
             
-            #line 119 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 155 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         foreach(var member in this.Structure.Members)
         {
@@ -309,7 +391,7 @@ protected override bool IsProcessing
             #line hidden
             this.Write("        ///<summary>\r\n        ///Raised when an ");
             
-            #line 126 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 162 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
@@ -317,21 +399,21 @@ protected override bool IsProcessing
             this.Write(" event is received\r\n        ///</summary>\r\n        public event EventHandler<Even" +
                     "tStreamEventReceivedArgs<");
             
-            #line 128 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 164 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
             #line hidden
             this.Write(">> ");
             
-            #line 128 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 164 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write("Received;\r\n");
             
-            #line 129 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 165 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
             }
 
@@ -339,7 +421,7 @@ protected override bool IsProcessing
             #line default
             #line hidden
             
-            #line 132 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 168 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
         }
 
@@ -349,7 +431,7 @@ protected override bool IsProcessing
             this.Write("\r\n        /// <summary>\r\n        /// Construct an instance\r\n        /// </summary" +
                     ">\r\n        /// <param name=\"stream\"></param>        \r\n        public ");
             
-            #line 140 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 176 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -365,7 +447,7 @@ protected override bool IsProcessing
         /// <param name=""eventStreamDecoder""></param>
         public ");
             
-            #line 149 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 185 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -394,7 +476,7 @@ protected override bool IsProcessing
                 var _ =
 ");
             
-            #line 171 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 207 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
                 if(isResponse)
 
@@ -403,7 +485,7 @@ protected override bool IsProcessing
             #line hidden
             this.Write("                    RaiseEvent(InitialResponseReceived, ev) ||\r\n");
             
-            #line 175 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 211 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
                 else if(isRequest)
 
@@ -412,7 +494,7 @@ protected override bool IsProcessing
             #line hidden
             this.Write("                    RaiseEvent(InitialRequestReceived,ev) ||\r\n");
             
-            #line 179 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 215 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
 
                 var eventMembers = this.Structure.Members.Where(m => m.ModelShape.IsEvent).ToArray();
@@ -424,14 +506,14 @@ protected override bool IsProcessing
             #line hidden
             this.Write("                    RaiseEvent(");
             
-            #line 185 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 221 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(eventMembers[0].PropertyName));
             
             #line default
             #line hidden
             this.Write("Received,ev);\r\n");
             
-            #line 186 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 222 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
                 }
                 else if (eventMembers.Length > 1)
@@ -444,14 +526,14 @@ protected override bool IsProcessing
             #line hidden
             this.Write("                    RaiseEvent(");
             
-            #line 193 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 229 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(eventMembers[i].PropertyName));
             
             #line default
             #line hidden
             this.Write("Received,ev) ||\r\n");
             
-            #line 194 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 230 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
                     }
 
@@ -460,14 +542,14 @@ protected override bool IsProcessing
             #line hidden
             this.Write("                    RaiseEvent(");
             
-            #line 197 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 233 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(eventMembers.Last().PropertyName));
             
             #line default
             #line hidden
             this.Write("Received,ev);\r\n");
             
-            #line 198 "C:\codebase\v3\AWSDotNetPublic\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
+            #line 234 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\EventStreamGenerator.tt"
 
                 }
 
diff --git a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.tt b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.tt
index f0898a735b8e..ae8709b6b001 100644
--- a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/EventStreamGenerator.tt
@@ -47,11 +47,30 @@
 <#
         foreach(var member in this.Structure.Members)
         {
-        if(member.ModelShape.IsEvent)
+            if(member.ModelShape.IsEvent)
             {
+                if (protocol == "Json")
+                {
 #>
-            {"<#=member.PropertyName#>", payload => new <#=member.DetermineType()#>Unmarshaller().Unmarshall(EventStreamUtils.ConvertMessageTo<#=protocol#>Context(payload))},
+            {"<#=member.PropertyName#>", payload => 
+                {
+                    var context = EventStreamUtils.ConvertMessageTo<#=protocol#>Context(payload);
+                    var reader = new StreamingUtf8JsonReader(context.Stream);
+                    return new <#=member.DetermineType()#>Unmarshaller().Unmarshall(context, ref reader);
+                }
+            },
 <#
+                }
+                else if (protocol == "Xml")
+                {
+#>
+            {"<#=member.PropertyName#>", payload => new <#=member.DetermineType()#>Unmarshaller().Unmarshall(context);},
+<#
+                }
+                else
+                {
+                    throw new NotImplementedException("The given protocol is not supported");
+                }
             }
         }
 #>
@@ -67,9 +86,26 @@
         {
             if(member.ModelShape.IsException)
             {
+                if (protocol == "Json")
+                {
+#>
+                    {"<#=member.PropertyName#>", payload => 
+                        {
+                            var context = EventStreamUtils.ConvertMessageTo<#=protocol#>Context(payload);
+                            var reader = new StreamingUtf8JsonReader(context.Stream);
+                            return new <#=this.Config.ClassName#>EventStreamException(Encoding.UTF8.GetString(payload.Payload), new <#=member.ModelShape#>Unmarshaller().Unmarshall(context, ref reader));
+                        }
+                    },
+<#
+                }
+                else if (protocol == "Xml")
+                {
 #>
             { "<#=member.PropertyName#>", payload => new <#=this.Config.ClassName#>EventStreamException(Encoding.UTF8.GetString(payload.Payload), new <#=member.ModelShape#>Unmarshaller().Unmarshall(EventStreamUtils.ConvertMessageTo<#=protocol#>Context(payload))) },
 <#
+                }
+                else
+                    throw new NotImplementedException("The given protocol is not supported");
             }
         }
 #>
diff --git a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.cs b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.cs
index e2d4572a6af7..e47f73e6b866 100644
--- a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.cs
+++ b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.cs
@@ -79,9 +79,9 @@ public override string TransformText()
             #line default
             #line hidden
             this.Write(".Model.Internal.MarshallTransformations;\r\nusing Amazon.Runtime.EventStreams.Utils" +
-                    ";\r\n");
+                    ";\r\nusing Amazon.Runtime.Internal.Util;\r\n");
             
-            #line 38 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 39 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
 }
 
@@ -90,14 +90,14 @@ public override string TransformText()
             #line hidden
             this.Write("\r\n#pragma warning disable CS0612,CS0618,CS1570\r\nnamespace ");
             
-            #line 43 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 44 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Config.Namespace));
             
             #line default
             #line hidden
             this.Write(".Model\r\n{\r\n");
             
-            #line 45 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 46 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
   
     if(this.StructureType == StructureType.Request)
         this.FormatOperationRequestDocumentation(this.Operation);
@@ -111,14 +111,14 @@ public override string TransformText()
             #line hidden
             this.Write("    /// <summary>\r\n    /// This is the response object from the ");
             
-            #line 54 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 55 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.Name));
             
             #line default
             #line hidden
             this.Write(" operation.\r\n    /// </summary>\r\n");
             
-            #line 56 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 57 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
     }
     else
@@ -128,7 +128,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 61 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 62 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
       
     if(this.Structure != null && this.Structure.IsDeprecated)
         {
@@ -138,14 +138,14 @@ public override string TransformText()
             #line hidden
             this.Write("    [Obsolete(\"");
             
-            #line 65 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 66 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.DeprecationMessage));
             
             #line default
             #line hidden
             this.Write("\")]\r\n");
             
-            #line 66 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 67 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         }
     if(this.Structure is ExceptionShape)
@@ -156,7 +156,7 @@ public override string TransformText()
             #line hidden
             this.Write("    #if !NETSTANDARD\r\n    [Serializable]\r\n    #endif\r\n");
             
-            #line 74 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 75 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         }
 
@@ -164,7 +164,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 77 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 78 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
 
     if(this.Structure != null && this.Structure.IsEventStream)
@@ -181,14 +181,14 @@ public override string TransformText()
             #line hidden
             this.Write("    ");
             
-            #line 88 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 89 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(EventStreamOutput));
             
             #line default
             #line hidden
             this.Write("\r\n");
             
-            #line 89 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 90 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
     }
 
@@ -196,7 +196,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 92 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 93 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
     bool hasStreamingMember = this.Structure?.Members.Any(member => member.Shape.IsStreaming) ?? false;
         
@@ -214,20 +214,20 @@ public override string TransformText()
             #line hidden
             this.Write("    public partial class ");
             
-            #line 104 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 105 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.ClassName));
             
             #line default
             #line hidden
             
-            #line 104 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 105 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.BaseClassString));
             
             #line default
             #line hidden
             this.Write(", IDisposable\r\n    {\r\n");
             
-            #line 106 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 107 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         }
     else 
@@ -237,7 +237,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 111 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 112 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         if( (this.Structure == null) || (structureIsNotEventStream))
         {
@@ -247,20 +247,20 @@ public override string TransformText()
             #line hidden
             this.Write("    public partial class ");
             
-            #line 115 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 116 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.ClassName));
             
             #line default
             #line hidden
             
-            #line 115 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 116 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.BaseClassString));
             
             #line default
             #line hidden
             this.Write("\r\n");
             
-            #line 116 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 117 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
             if(structureIsEvent)
             {
@@ -270,7 +270,7 @@ public override string TransformText()
             #line hidden
             this.Write("        : IEventStreamEvent\r\n");
             
-            #line 121 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 122 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
             }
 
@@ -279,7 +279,7 @@ public override string TransformText()
             #line hidden
             this.Write("    {\r\n");
             
-            #line 125 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 126 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         }
 
@@ -287,7 +287,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 128 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 129 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
     }
 
@@ -295,7 +295,7 @@ public override string TransformText()
             #line default
             #line hidden
             
-            #line 131 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 132 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         if(structureIsNotEventStream)
         {
@@ -307,28 +307,28 @@ public override string TransformText()
             #line hidden
             this.Write("        private ");
             
-            #line 137 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 138 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write(" _response;\r\n\r\n        /// <summary>\r\n        /// Gets and sets the ");
             
-            #line 140 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 141 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write(" property.\r\n        /// </summary>\r\n        public ");
             
-            #line 142 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 143 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
             #line hidden
             this.Write(" ");
             
-            #line 142 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 143 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Structure.Name));
             
             #line default
@@ -336,7 +336,7 @@ public override string TransformText()
             this.Write("\r\n        {\r\n            get { return this._response; }\r\n            set { this._" +
                     "response = value; }\r\n        }\r\n");
             
-            #line 147 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 148 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
             }
             else
@@ -359,27 +359,27 @@ public override string TransformText()
             #line hidden
             this.Write("        private ");
             
-            #line 164 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 165 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
             #line hidden
             this.Write(" ");
             
-            #line 164 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 165 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             
-            #line 164 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 165 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.IsCollection ? string.Format(" = AWSConfigs.InitializeCollections ? new {0}() : null;", member.DetermineType()) : ";"));
             
             #line default
             #line hidden
             this.Write("\r\n");
             
-            #line 165 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 166 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 }
 
@@ -388,7 +388,7 @@ public override string TransformText()
             #line hidden
             this.Write("\r\n");
             
-            #line 169 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 170 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 AddSimpleRequestConstructors(this.ClassName, this.Structure, this.Config.Namespace);
 
@@ -403,14 +403,14 @@ public override string TransformText()
             #line hidden
             this.Write("        private RetryableDetails _retryableDetails = new RetryableDetails(");
             
-            #line 178 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 179 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(exceptionShape.Throttling.ToString().ToLower()));
             
             #line default
             #line hidden
             this.Write(");\r\n");
             
-            #line 179 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 180 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
 
             
@@ -418,7 +418,7 @@ public override string TransformText()
             #line hidden
             this.Write("\r\n");
             
-            #line 182 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 183 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
 
@@ -645,7 +645,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             this.Write("        }\r\n#endif\r\n");
             this.Write("\r\n");
             
-            #line 187 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 188 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 }
                 foreach(var member in this.Structure.Members)
@@ -665,13 +665,13 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line default
             #line hidden
             
-            #line 202 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 203 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
  this.FormatPropertyDocumentation(member); 
             
             #line default
             #line hidden
             
-            #line 203 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 204 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
       
                     if(member.IsDeprecated)
                     {
@@ -681,14 +681,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        [Obsolete(\"");
             
-            #line 207 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 208 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DeprecationMessage));
             
             #line default
             #line hidden
             this.Write("\")]\r\n");
             
-            #line 208 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 209 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
 
@@ -717,14 +717,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        [AWSProperty(");
             
-            #line 231 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 232 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(string.Join(", ", propertyAttributes)));
             
             #line default
             #line hidden
             this.Write(")]\r\n");
             
-            #line 232 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 233 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
 
@@ -736,48 +736,55 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        ");
             
-            #line 238 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.AccessModifier));
             
             #line default
             #line hidden
             this.Write(" ");
             
-            #line 238 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName.Equals("Equals") || (this.Structure is ExceptionShape && member.PropertyName.Equals("Retryable")) ? "new " : ""));
             
             #line default
             #line hidden
             
-            #line 238 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
             
             #line default
             #line hidden
             this.Write(" ");
             
-            #line 238 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 239 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write("\r\n        {\r\n            get { return this.");
             
-            #line 240 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 241 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write("; }\r\n            set { this.");
             
-            #line 241 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 242 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.IsBackwardsCompatibleDateTimeProperty ? "this." + member.BackwardCompatibilityVariableName + " = " : ""));
+            
+            #line default
+            #line hidden
+            this.Write("this.");
+            
+            #line 242 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(" = value; }\r\n        }\r\n\r\n");
             
-            #line 244 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 245 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     if (member.EmitIsSetProperties)
                     {
@@ -788,7 +795,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             this.Write("        /// <summary>\r\n        /// This property is set to true if the property <" +
                     "seealso cref=\"");
             
-            #line 249 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 250 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
@@ -804,7 +811,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
         /// </returns>
 ");
             
-            #line 258 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 259 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
       
                         if(member.IsDeprecated)
                         {
@@ -814,14 +821,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        [Obsolete(\"");
             
-            #line 262 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 263 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.DeprecationMessage));
             
             #line default
             #line hidden
             this.Write("\")]\r\n");
             
-            #line 263 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 264 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         }
 
@@ -830,7 +837,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        public bool Is");
             
-            #line 266 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 267 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
@@ -838,7 +845,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             this.Write("Set\r\n        {\r\n            get\r\n            {\r\n                return Amazon.Uti" +
                     "l.Internal.InternalSDKUtils.GetIsSet(this.");
             
-            #line 270 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 271 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
@@ -846,14 +853,41 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             this.Write(");\r\n            }\r\n            set\r\n            {\r\n                Amazon.Util.In" +
                     "ternal.InternalSDKUtils.SetIsSet(value, ref this.");
             
-            #line 274 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 275 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(");\r\n            }\r\n        }\r\n\r\n");
             
-            #line 278 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 276 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                        if(member.IsBackwardsCompatibleDateTimeProperty)
+                        {
+
+            
+            #line default
+            #line hidden
+            this.Write("  \r\n                Amazon.Util.Internal.InternalSDKUtils.SetIsSet(value, ref thi" +
+                    "s.");
+            
+            #line 280 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityVariableName));
+            
+            #line default
+            #line hidden
+            this.Write(");\r\n");
+            
+            #line 281 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                        }
+
+            
+            #line default
+            #line hidden
+            this.Write("            }\r\n        }\r\n\r\n");
+            
+            #line 287 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
 
@@ -862,21 +896,21 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        // Check to see if ");
             
-            #line 281 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 290 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write(" property is set\r\n        internal bool IsSet");
             
-            #line 282 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 291 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write("()\r\n        {\r\n");
             
-            #line 284 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 293 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     if (member.EmitIsSetProperties)
                     {
@@ -886,14 +920,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return this.Is");
             
-            #line 288 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 297 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
             
             #line default
             #line hidden
             this.Write("Set; \r\n");
             
-            #line 289 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 298 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
                     else if (member.IsNullable)
@@ -904,14 +938,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return this.");
             
-            #line 294 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 303 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(".HasValue; \r\n");
             
-            #line 295 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 304 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
                     else if (member.IsList && (member.MarshallLocation == MarshallLocation.Header || member.MarshallLocation == MarshallLocation.Headers))
@@ -924,21 +958,21 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return this.");
             
-            #line 302 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 311 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(" != null && this.");
             
-            #line 302 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 311 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(".Count > 0;\r\n");
             
-            #line 303 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 312 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
                     else if (member.IsMap || member.IsList)
@@ -949,21 +983,21 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return this.");
             
-            #line 308 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 317 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(" != null && (this.");
             
-            #line 308 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 317 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(".Count > 0 || !AWSConfigs.InitializeCollections); \r\n");
             
-            #line 309 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 318 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
                     else if (member.IsDocument)
@@ -974,14 +1008,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return !this.");
             
-            #line 314 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 323 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(".IsNull();\r\n");
             
-            #line 315 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 324 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
                     else
@@ -996,14 +1030,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return !string.IsNullOrEmpty(this.");
             
-            #line 324 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 333 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(");\r\n");
             
-            #line 325 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 334 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         }
                         else
@@ -1014,14 +1048,14 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return this.");
             
-            #line 330 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 339 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(" != null;\r\n");
             
-            #line 331 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 340 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         }
                     }
@@ -1031,7 +1065,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        }\r\n\r\n");
             
-            #line 337 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 346 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 }
 
@@ -1045,7 +1079,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
                     "   /// </summary>\r\n        /// <returns>A signer for this request.</returns>\r\n  " +
                     "      override protected AbstractAWSSigner CreateSigner()\r\n        {\r\n");
             
-            #line 349 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 358 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     switch (this.Operation.AuthType.Value)
                     {
@@ -1056,7 +1090,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return new NullSigner();\r\n");
             
-            #line 355 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 364 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         break;
                         case OperationAuthType.V4:
@@ -1066,7 +1100,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return new AWS4Signer();\r\n");
             
-            #line 360 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 369 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         break;
                         case OperationAuthType.V4UnsignedBody:
@@ -1076,7 +1110,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return new AWS4Signer(false);\r\n");
             
-            #line 365 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 374 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         break;
                         case OperationAuthType.Bearer:
@@ -1086,7 +1120,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("            return new BearerTokenSigner();\r\n");
             
-            #line 370 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 379 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         break;
                         default:
@@ -1098,7 +1132,7 @@ public override void GetObjectData(System.Runtime.Serialization.SerializationInf
             #line hidden
             this.Write("        }\r\n");
             
-            #line 377 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 386 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 }
                 // Flexible checksum overrides to allow response validation configuration on the request
@@ -1119,7 +1153,7 @@ protected override CoreChecksumResponseBehavior CoreChecksumMode
             {
                 if (IsSet");
             
-            #line 391 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 400 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.ChecksumConfiguration.RequestValidationModeMember));
             
             #line default
@@ -1127,7 +1161,7 @@ protected override CoreChecksumResponseBehavior CoreChecksumMode
             this.Write("())\r\n                {\r\n                    return (CoreChecksumResponseBehavior)" +
                     "Enum.Parse(typeof(CoreChecksumResponseBehavior), this.");
             
-            #line 393 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 402 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(this.Operation.ChecksumConfiguration.RequestValidationModeMember));
             
             #line default
@@ -1137,7 +1171,7 @@ protected override CoreChecksumResponseBehavior CoreChecksumMode
                     "ithm> _supportedChecksumAlgorithms = new List<CoreChecksumAlgorithm>\r\n        {\r" +
                     "\n            ");
             
-            #line 402 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 411 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(string.Join(", ", Operation.ChecksumConfiguration?.ResponseAlgorithms?.Select(s => $"CoreChecksumAlgorithm.{s}").ToArray())));
             
             #line default
@@ -1152,10 +1186,261 @@ protected override CoreChecksumResponseBehavior CoreChecksumMode
 #endregion
 ");
             
-            #line 410 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 419 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 }
 
+                if (this.Structure.Members.Any(m => !m.IsExcluded && m.IsBackwardsCompatibleDateTimeProperty))
+                {
+
+            
+            #line default
+            #line hidden
+            this.Write("#region Backwards compatible properties\r\n");
+            
+            #line 426 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                    foreach(var member in this.Structure.Members)
+                    {
+                        if (member.IsExcluded || !member.IsBackwardsCompatibleDateTimeProperty)
+                            continue;
+
+            
+            #line default
+            #line hidden
+            this.Write("        private ");
+            
+            #line 432 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
+            
+            #line default
+            #line hidden
+            this.Write(" ");
+            
+            #line 432 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityVariableName));
+            
+            #line default
+            #line hidden
+            
+            #line 432 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.IsCollection ? string.Format(" = AWSConfigs.InitializeCollections ? new {0}() : null;", member.DetermineType()) : ";"));
+            
+            #line default
+            #line hidden
+            this.Write("\r\n");
+            
+            #line 433 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                    }
+
+            
+            #line default
+            #line hidden
+            this.Write("\r\n");
+            
+            #line 437 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                    foreach(var member in this.Structure.Members)
+                    {
+                        if (member.IsExcluded || !member.IsBackwardsCompatibleDateTimeProperty)
+                            continue;
+
+            
+            #line default
+            #line hidden
+            
+            #line 443 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+ this.FormatPropertyDocumentation(member, "This property is deprecated. Setting this property results in non-UTC DateTimes " +
+        "not being marshalled correctly. Use " + member.PropertyName + " instead. Setting either " + member.BackwardCompatibilityPropertyName +
+        " or " + member.PropertyName + " results in both " + member.BackwardCompatibilityPropertyName + " and " + 
+        member.PropertyName + " being assigned, the latest assignment to either one of the two property is reflected in " +
+        "the value of both. " + member.BackwardCompatibilityPropertyName + " is provided for backwards compatibility only " +
+        "and assigning a non-Utc DateTime to it results in the wrong timestamp being passed to the service.");
+            
+            #line default
+            #line hidden
+            this.Write("        [Obsolete(\"Setting this property results in non-UTC DateTimes not being m" +
+                    "arshalled correctly. \" +\r\n            \"Use ");
+            
+            #line 450 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" instead. Setting either ");
+            
+            #line 450 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" or ");
+            
+            #line 450 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" results in both ");
+            
+            #line 450 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" and \" +\r\n            \"");
+            
+            #line 451 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" being assigned, the latest assignment to either one of the two property is \" + \r" +
+                    "\n            \"reflected in the value of both. ");
+            
+            #line 452 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" is provided for backwards compatibility only and \" +\r\n            \"assigning a n" +
+                    "on-Utc DateTime to it results in the wrong timestamp being passed to the service" +
+                    ".\", false)]\r\n        ");
+            
+            #line 454 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.AccessModifier));
+            
+            #line default
+            #line hidden
+            this.Write(" ");
+            
+            #line 454 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.DetermineType()));
+            
+            #line default
+            #line hidden
+            
+            #line 454 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.UseNullable ? "?" : ""));
+            
+            #line default
+            #line hidden
+            this.Write(" ");
+            
+            #line 454 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write("\r\n        {\r\n            get { return this.");
+            
+            #line 456 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityVariableName));
+            
+            #line default
+            #line hidden
+            this.Write(".GetValueOrDefault(); }\r\n            set\r\n            {\r\n                this.");
+            
+            #line 459 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityVariableName));
+            
+            #line default
+            #line hidden
+            this.Write(" = value;\r\n                if (value != null)\r\n                {\r\n               " +
+                    "     this.");
+            
+            #line 462 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
+            
+            #line default
+            #line hidden
+            this.Write(" = new DateTime(value.Value.Ticks, DateTimeKind.Utc);\r\n                }\r\n       " +
+                    "         else\r\n                {\r\n                    this.");
+            
+            #line 466 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
+            
+            #line default
+            #line hidden
+            this.Write(" = null;\r\n                }\r\n            }\r\n        }\r\n");
+            
+            #line 470 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                        if (member.EmitIsSetProperties)
+                        {
+
+            
+            #line default
+            #line hidden
+            this.Write("        /// <summary>\r\n        /// This property is set to true if the property <" +
+                    "seealso cref=\"");
+            
+            #line 475 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(@"""/>
+        /// is set; false otherwise.
+        /// This property can be used to determine if the related property
+        /// was returned by a service response or if the related property
+        /// should be sent to the service during a service call.
+        /// </summary>
+        /// <returns>
+        /// True if the related property was set or will be sent to a service; false otherwise.
+        /// </returns>
+        [Obsolete(""Setting ");
+            
+            #line 484 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" results in non-UTC DateTimes not being marshalled correctly. Use ");
+            
+            #line 484 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write(" instead.\", false)]\r\n        public bool Is");
+            
+            #line 485 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.BackwardCompatibilityPropertyName));
+            
+            #line default
+            #line hidden
+            this.Write("Set\r\n        {\r\n            get\r\n            {\r\n                return this.Is");
+            
+            #line 489 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write("Set;\r\n            }\r\n            set\r\n            {\r\n                this.Is");
+            
+            #line 493 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            this.Write(this.ToStringHelper.ToStringWithCulture(member.PropertyName));
+            
+            #line default
+            #line hidden
+            this.Write("Set = value;;\r\n            }\r\n        }\r\n");
+            
+            #line 496 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                        }
+                    }
+
+
+            
+            #line default
+            #line hidden
+            this.Write("#endregion\r\n");
+            
+            #line 502 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+
+                }
                 if (this.Structure is ExceptionShape)
                 {
                     var exceptionShape = (ExceptionShape)this.Structure;
@@ -1178,7 +1463,7 @@ public override RetryableDetails Retryable
         }
 ");
             
-            #line 430 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 521 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                     }
                 }
@@ -1193,7 +1478,7 @@ public override RetryableDetails Retryable
             #line hidden
             this.Write("\r\n");
             
-            #line 440 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 531 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         }
         if (this.StructureType == StructureType.Response && hasStreamingMember) 
@@ -1227,7 +1512,7 @@ protected virtual void Dispose(bool disposing)
             {
 ");
             
-            #line 468 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 559 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                 if (this.Structure != null) 
                 {
@@ -1241,21 +1526,21 @@ protected virtual void Dispose(bool disposing)
             #line hidden
             this.Write("                this.");
             
-            #line 476 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 567 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write("?.Dispose();\r\n                this.");
             
-            #line 477 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 568 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
             this.Write(this.ToStringHelper.ToStringWithCulture(member.VariableName));
             
             #line default
             #line hidden
             this.Write(" = null;\r\n");
             
-            #line 478 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 569 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
                         }
                     }
@@ -1267,7 +1552,7 @@ protected virtual void Dispose(bool disposing)
             this.Write("            }\r\n\r\n            this._disposed = true;\r\n         }\r\n\r\n         #endr" +
                     "egion\r\n");
             
-            #line 489 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+            #line 580 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
         }
 
@@ -1278,7 +1563,7 @@ protected virtual void Dispose(bool disposing)
             return this.GenerationEnvironment.ToString();
         }
         
-        #line 495 "C:\Dev\worktrees\fixdatetimes\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
+        #line 586 "C:\Dev\Repos\aws-sdk-net-staging\generator\ServiceClientGeneratorLib\Generators\SourceFiles\StructureGenerator.tt"
 
     // Set to true when the service model specifies a shape that should be wrapped in a response. ElastiCache CreateCacheCluster is an example of this.
     public bool IsWrapped { get; set; }
diff --git a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.tt b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.tt
index 1798cf27ebfd..3389116870cc 100644
--- a/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.tt
+++ b/generator/ServiceClientGeneratorLib/Generators/SourceFiles/StructureGenerator.tt
@@ -35,6 +35,7 @@ using Amazon.Runtime.EventStreams;
 using Amazon.Runtime.EventStreams.Internal;
 using <#=this.Config.Namespace#>.Model.Internal.MarshallTransformations;
 using Amazon.Runtime.EventStreams.Utils;
+using Amazon.Runtime.Internal.Util;
 <#
 }
 #>
diff --git a/generator/ServiceClientGeneratorLib/Member.cs b/generator/ServiceClientGeneratorLib/Member.cs
index 8098ef115b11..134dcd48320b 100644
--- a/generator/ServiceClientGeneratorLib/Member.cs
+++ b/generator/ServiceClientGeneratorLib/Member.cs
@@ -631,16 +631,26 @@ string GetTypeUnmarshallerName(JsonData extendedData, bool useNullable = true)
                     var keyTypeUnmarshaller = GetTypeUnmarshallerName(memberShape[Shape.KeyKey], useNullable);
                     var valueType = DetermineType(memberShape[Shape.ValueKey], true, useNullable);
                     var valueTypeUnmarshaller = GetTypeUnmarshallerName(memberShape[Shape.ValueKey], useNullable);
-
-                    return string.Format("DictionaryUnmarshaller<{0}, {1}, {2}, {3}>",
-                        keyType, valueType, keyTypeUnmarshaller, valueTypeUnmarshaller);
+                    if (this.model.Type == ServiceType.Json || this.model.Type == ServiceType.Rest_Json)
+                        return string.Format("JsonDictionaryUnmarshaller<{0}, {1}, {2}, {3}>",
+                            keyType, valueType, keyTypeUnmarshaller, valueTypeUnmarshaller);
+                    else if (this.model.Type == ServiceType.Query || this.model.Type == ServiceType.Rest_Xml)
+                        return string.Format("XmlDictionaryUnmarshaller<{0}, {1}, {2}, {3}>",
+                            keyType, valueType, keyTypeUnmarshaller, valueTypeUnmarshaller);
+                    else
+                        throw new Exception("Unknown protocol type");
                 case "list":
                     var listType = DetermineType(memberShape[Member.MemberKey], true, useNullable);
                     var listTypeUnmarshaller = GetTypeUnmarshallerName(memberShape[Member.MemberKey], useNullable);
-
-                    return string.Format("ListUnmarshaller<{0}, {1}>",
+                    if (this.model.Type == ServiceType.Json || this.model.Type == ServiceType.Rest_Json)
+                        return string.Format("JsonListUnmarshaller<{0},{1}>",listType, listTypeUnmarshaller);
+                    if (this.model.Type == ServiceType.Rest_Xml || this.model.Type == ServiceType.Query)
+                        return string.Format("XmlListUnmarshaller<{0}, {1}>",
                         listType, listTypeUnmarshaller);
-
+                    else
+                    {
+                        throw new Exception("Unknown protocol type");
+                    }
                 case "decimal":
                     throw new Exception(UnhandledTypeDecimalErrorMessage);
 
@@ -726,13 +736,14 @@ public string DetermineTypeUnmarshallerInstantiate(JsonData extendedData, string
                         isFlat = false;
                     }
 
-                    if (this.model.Type == ServiceType.Json 
-                        || this.model.Type == ServiceType.Rest_Json 
-                        || (this.model.Type == ServiceType.Rest_Xml && !isFlat))
-                        return string.Format("new DictionaryUnmarshaller<{0}, {1}, {2}, {3}>(StringUnmarshaller.Instance, {5})",
+                    if (this.model.Type == ServiceType.Json || this.model.Type == ServiceType.Rest_Json)
+                        return string.Format("new JsonDictionaryUnmarshaller<{0}, {1}, {2}, {3}>(StringUnmarshaller.Instance, {5})",
+                            keyType, valueType, keyTypeUnmarshaller, valueTypeUnmarshaller, keyTypeUnmarshallerInstantiate, valueTypeUnmarshallerInstantiate);
+                    else if (this.model.Type == ServiceType.Rest_Xml && !isFlat)
+                        return string.Format("new XmlDictionaryUnmarshaller<{0}, {1}, {2}, {3}>(StringUnmarshaller.Instance, {5})",
                             keyType, valueType, keyTypeUnmarshaller, valueTypeUnmarshaller, keyTypeUnmarshallerInstantiate, valueTypeUnmarshallerInstantiate);
                     else
-                        return string.Format("new KeyValueUnmarshaller<{0}, {1}, {2}, {3}>(StringUnmarshaller.Instance, {5})",
+                        return string.Format("new XmlKeyValueUnmarshaller<{0}, {1}, {2}, {3}>(StringUnmarshaller.Instance, {5})",
                             keyType, valueType, keyTypeUnmarshaller, valueTypeUnmarshaller, keyTypeUnmarshallerInstantiate, valueTypeUnmarshallerInstantiate);
                 case "list":
                     var listType = DetermineType(memberShape[Shape.MemberKey], true, false);
@@ -740,7 +751,7 @@ public string DetermineTypeUnmarshallerInstantiate(JsonData extendedData, string
                     var listTypeUnmarshallerInstantiate = DetermineTypeUnmarshallerInstantiate(memberShape[Shape.MemberKey], typeNode.ToString(), false);
 
                     if (this.model.Type == ServiceType.Json || this.model.Type == ServiceType.Rest_Json)
-                        return string.Format("new ListUnmarshaller<{0}, {1}>({2})",
+                        return string.Format("new JsonListUnmarshaller<{0}, {1}>({2})",
                             listType, listTypeUnmarshaller, listTypeUnmarshallerInstantiate);
                     else if ((this.model.Type == ServiceType.Query || this.model.Type == ServiceType.Rest_Xml) && $"{listTypeUnmarshaller}.Instance" != listTypeUnmarshallerInstantiate)
                         return $"new {listTypeUnmarshaller}({listTypeUnmarshallerInstantiate})";
diff --git a/sdk/src/Core/AWSConfigs.cs b/sdk/src/Core/AWSConfigs.cs
index 8cd2f44b68b7..11802ed7313d 100644
--- a/sdk/src/Core/AWSConfigs.cs
+++ b/sdk/src/Core/AWSConfigs.cs
@@ -243,14 +243,34 @@ public static string AWSProfilesLocation
         }
 
         #endregion
+        #region StreamingUtf8JsonReaderBufferSize
 
-
-        #region SDK Cache
+        /// <summary>
+        /// Key for the StreamingUtf8JsonReaderBufferSize property.
+        /// <seealso cref="Amazon.AWSConfigs.StreamingUtf8JsonReaderBufferSize"/>"/>
+        /// </summary>
+        public const string StreamingUtf8JsonReaderBufferSizeKey = "StreamingUtf8JsonReaderBufferSize";
 
         /// <summary>
-        /// Key for the UseSdkCache property.
-        /// <seealso cref="Amazon.AWSConfigs.UseSdkCache"/>
+        /// Configures the default buffer size for the the StreamingUtf8JsonReader/>
+        /// used for buffering data from the stream passed into its constructor. If this isn't set, the SDK will default to 4096 bytes.
+        /// 
+        /// Setting this property is not thread safe and should only be set at application startup.
         /// </summary>
+        public static int? StreamingUtf8JsonReaderBufferSize
+        {
+            get { return _rootConfig.StreamingUtf8JsonReaderBufferSize; }
+            set { _rootConfig.StreamingUtf8JsonReaderBufferSize = value; }
+        }
+
+        #endregion
+
+            #region SDK Cache
+
+            /// <summary>
+            /// Key for the UseSdkCache property.
+            /// <seealso cref="Amazon.AWSConfigs.UseSdkCache"/>
+            /// </summary>
         public const string UseSdkCacheKey = "AWSCache";
 
         /// <summary>
diff --git a/sdk/src/Core/AWSSDK.Core.NetFramework.csproj b/sdk/src/Core/AWSSDK.Core.NetFramework.csproj
index 607c7a130b66..d6481420e5c9 100644
--- a/sdk/src/Core/AWSSDK.Core.NetFramework.csproj
+++ b/sdk/src/Core/AWSSDK.Core.NetFramework.csproj
@@ -71,10 +71,6 @@
   <ItemGroup>
     <PackageReference Include="System.Buffers" Version="4.5.1" />
     <PackageReference Include="System.Memory" Version="4.5.5" />
-  <!-- Powershell (pwsh) will have a preloaded version of System.Text.Json that is older than
-  the version we will ship in core nuget packages and dlls, so we compile with an  older version of STJ
-  but ship nuget packages and dlls with newer versions of STJ. If we don't do this then sdk assemblies will fail
-  to load in powershell due to unsupported versions -->
     <PackageReference Include="System.Text.Json" Version="6.0.11" />
   </ItemGroup>
   <Import Project="overrides.targets"/>
diff --git a/sdk/src/Core/AWSSDK.Core.NetStandard.csproj b/sdk/src/Core/AWSSDK.Core.NetStandard.csproj
index 6e3f4ee951de..efc193a0877e 100644
--- a/sdk/src/Core/AWSSDK.Core.NetStandard.csproj
+++ b/sdk/src/Core/AWSSDK.Core.NetStandard.csproj
@@ -83,9 +83,6 @@
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="8.0.0" />
     <PackageReference Include="System.Buffers" Version="4.5.1" />
     <PackageReference Include="System.Memory" Version="4.5.5" />
-    <!-- Powershell 7+ already has a preloaded version of system text json which is older than the version 
-    we ship in nuget packages and dlls. To ensure SDK assemblies can be loaded in powershell, we must compile with 
-    an older version of System.Text.Json.  -->
     <PackageReference Include="System.Text.Json" Version="6.0.11" />
   </ItemGroup>
     <Import Project="overrides.targets"/>
diff --git a/sdk/src/Core/Amazon.Runtime/Documents/Internal/Transform/DocumentUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Documents/Internal/Transform/DocumentUnmarshaller.cs
index cdc85503b461..0463ee245144 100644
--- a/sdk/src/Core/Amazon.Runtime/Documents/Internal/Transform/DocumentUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Documents/Internal/Transform/DocumentUnmarshaller.cs
@@ -18,77 +18,80 @@
 using System.Collections.Generic;
 using System.Collections.Specialized;
 using System.Linq;
+using System.Text.Json;
 using Amazon.Runtime.Internal.Transform;
-using ThirdParty.Json.LitJson;
+using Amazon.Runtime.Internal.Util;
 
 namespace Amazon.Runtime.Documents.Internal.Transform
 {
     /// <summary>
-    /// Dedicated <see cref="IUnmarshaller{T,R}"/> for <see cref="Document"/>.
+    /// Dedicated <see cref="IJsonUnmarshaller{T,TJsonUnmarshallerContext}"/> for <see cref="Document"/>.
     /// </summary>
     /// <remarks>
     /// Per the Document Spec, Xml is not supported.
     /// </remarks>
-    public class DocumentUnmarshaller : IUnmarshaller<Document, JsonUnmarshallerContext>, IUnmarshaller<Document, XmlUnmarshallerContext>
+    public class DocumentUnmarshaller : IJsonUnmarshaller<Document, JsonUnmarshallerContext>
     {
         public static DocumentUnmarshaller Instance { get; } = new DocumentUnmarshaller();
         private DocumentUnmarshaller() { }
 
-        public Document Unmarshall(JsonUnmarshallerContext context)
+        public Document Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
             switch (context.CurrentTokenType)
             {
-                case JsonToken.Null:
-                case JsonToken.None:
+                case JsonTokenType.Null:
+                case JsonTokenType.None:
                     return new Document();
-                case JsonToken.Boolean:
-                    return new Document(bool.Parse(context.ReadText()));
-                case JsonToken.Double:
-                    return new Document(double.Parse(context.ReadText()));
-                case JsonToken.Int:
-                    return new Document(int.Parse(context.ReadText()));
-                case JsonToken.Long:
-                    return new Document(long.Parse(context.ReadText()));
-                case JsonToken.String:
-                    return new Document(context.ReadText());
-                case JsonToken.ArrayStart:
+                case JsonTokenType.True:
+                case JsonTokenType.False:
+                    return new Document(reader.Reader.GetBoolean());
+                case JsonTokenType.Number:
+                    if (reader.Reader.TryGetInt32(out int intValue))
+                    {
+                        return new Document(intValue);
+                    }
+                    else if (reader.Reader.TryGetInt64(out long longValue))
+                    {
+                        return new Document(longValue);
+                    }
+                    else if (reader.Reader.TryGetDouble(out double doubleValue))
+                    {
+                        return new Document(doubleValue);
+                    }
+                    else
+                    {
+                        throw new JsonException("Unsupported number type.");
+                    }
+                case JsonTokenType.String:
+                    return new Document(reader.Reader.GetString());
+                case JsonTokenType.StartArray:
                     var list = new List<Document>();
 
-                    while (!context.Peek(JsonToken.ArrayEnd))
-                        list.Add(Unmarshall(context));
+                    while (!context.Peek(JsonTokenType.EndArray, ref reader))
+                        list.Add(Unmarshall(context, ref reader));
 
-                    context.Read(); // Read ArrayEnd
+                    context.Read(ref reader); // Read ArrayEnd
                     return new Document(list);
-                case JsonToken.ObjectStart:
+                case JsonTokenType.StartObject:
                     var dict = new Dictionary<string, Document>();
 
-                    while (!context.Peek(JsonToken.ObjectEnd))
+                    while (!context.Peek(JsonTokenType.EndObject, ref reader))
                     {
                         // Only supported Object is Dictionary<string, Document>
 
-                        var key = StringUnmarshaller.Instance.Unmarshall(context);
-                        var value = Unmarshall(context);
+                        var key = StringUnmarshaller.Instance.Unmarshall(context, ref reader);
+                        var value = Unmarshall(context, ref reader);
 
                         dict.Add(key, value);
                     }
 
-                    context.Read(); // Read ObjectEnd
+                    context.Read(ref reader); // Read ObjectEnd
 
                     return new Document(dict);
                 default:
                     throw new ArgumentException($"Unknown JSON type: {context.CurrentTokenType}");
             }
         }
-
-        /// <remarks>
-        /// Document Types does not support xml.  However, Generic Type constraints for
-        /// <see cref="ListUnmarshaller{I,IUnmarshaller}"/> require implementing both
-        /// json and xml unmarshalling support.
-        /// </remarks>
-        Document IUnmarshaller<Document, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext input)
-        {
-            throw new NotImplementedException("Document is not supported in Xml Protocol");
-        }
     }
 }
\ No newline at end of file
diff --git a/sdk/src/Core/Amazon.Runtime/EventStreams/Internal/EventStreamUtils.cs b/sdk/src/Core/Amazon.Runtime/EventStreams/Internal/EventStreamUtils.cs
index 3087cec1a4d2..25196919639a 100644
--- a/sdk/src/Core/Amazon.Runtime/EventStreams/Internal/EventStreamUtils.cs
+++ b/sdk/src/Core/Amazon.Runtime/EventStreams/Internal/EventStreamUtils.cs
@@ -15,6 +15,7 @@
 
 using Amazon.Runtime.EventStreams.Internal;
 using Amazon.Runtime.Internal.Transform;
+using Amazon.Runtime.Internal.Util;
 using System;
 using System.Collections.Generic;
 using System.IO;
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IJsonErrorResponseUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IJsonErrorResponseUnmarshaller.cs
new file mode 100644
index 000000000000..7d6a1cef8ad8
--- /dev/null
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IJsonErrorResponseUnmarshaller.cs
@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Text.Json;
+using System.Threading.Tasks;
+using Amazon.Runtime.Internal.Util;
+
+namespace Amazon.Runtime.Internal.Transform
+{
+    /// <summary>
+    /// The interface for unmarshalling a json error response.
+    /// </summary>
+    /// <typeparam name="T">The type to unmarshall.</typeparam>
+    /// <typeparam name="TJsonUnmarshallerContext">The json unmarshaller context</typeparam>
+    public interface IJsonErrorResponseUnmarshaller<T, TJsonUnmarshallerContext>
+    {
+        /// <summary>
+        /// The unmarshall method accepts a context, the error response and a StreamingUTf8JsonReader and returns the modeled exception.
+        /// </summary>
+        /// <param name="context">The JSON Unmarshaller context</param>
+        /// <param name="errorResponse">The error response</param>
+        /// <param name="reader">The JSON reader</param>
+        /// <returns>T, the error shape that is unmarshalled from the JSON context</returns>
+        T Unmarshall(TJsonUnmarshallerContext context, ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader);
+    }
+}
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IJsonUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IJsonUnmarshaller.cs
new file mode 100644
index 000000000000..74d8d5584587
--- /dev/null
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IJsonUnmarshaller.cs
@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Text.Json;
+using System.Threading.Tasks;
+using Amazon.Runtime.Internal.Util;
+
+namespace Amazon.Runtime.Internal.Transform
+{
+    /// <summary>
+    /// Interface for JSON unmarshallers which unmarshall objects from response data.
+    /// The Unmarshallers are stateless, and only encode the rules for what data in
+    /// the JSON stream goes into what members of an object.
+    /// </summary>
+    /// <typeparam name="T">The type of object the unmarshaller returns</typeparam>
+    /// <typeparam name="TJsonUnmarshallerContext">The type of the Unmarshaller context. This can be any context that
+    /// inherits from JsonUnmarshallerContext or JsonUnmarshallerContext itself. The context contains the
+    /// state during parsing of the JSON stream.</typeparam>
+    public interface IJsonUnmarshaller<T, TJsonUnmarshallerContext>
+    {
+        /// <summary>
+        /// Given the current position in the JSON stream, extract a T.
+        /// </summary>
+        /// <param name="input">The JSON parsing context</param>
+        /// <param name="reader">The Utf8JsonReader in the System Text JSON namespace</param>
+        /// <returns>An object of type T populated with data from the JSON stream.</returns>
+        T Unmarshall(TJsonUnmarshallerContext input, ref StreamingUtf8JsonReader reader);
+    }
+}
\ No newline at end of file
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IResponseUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IResponseUnmarshaller.cs
index 675bd3122e16..78554f70d486 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IResponseUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IResponseUnmarshaller.cs
@@ -26,19 +26,26 @@ namespace Amazon.Runtime.Internal.Transform
     /// in the XML stream goes into what members of an object. 
     /// </summary>
     /// <typeparam name="T">The type of object the unmarshaller returns</typeparam>
-    /// <typeparam name="R">The type of the XML unmashaller context, which contains the
-    /// state of parsing the XML stream. Uaually an instance of 
+    /// <typeparam name="R">The type of the unmashaller context, which contains the
+    /// state of parsing the stream. Usually an instance of 
     /// <c>Amazon.Runtime.Internal.Transform.UnmarshallerContext</c>.</typeparam>
-    public interface IResponseUnmarshaller<T, R> : IUnmarshaller<T, R>
+    public interface IResponseUnmarshaller<T, R>
     {
         /// <summary>
         /// Extracts an exeption with data from an ErrorResponse.
         /// </summary>
-        /// <param name="input">The XML parsing context.</param>
+        /// <param name="input">The parsing context.</param>
         /// <param name="innerException">An inner exception to be included with the returned exception</param>
         /// <param name="statusCode">The HttpStatusCode from the ErrorResponse</param>
         /// <returns>Either an exception based on the ErrorCode from the ErrorResponse, or the 
         /// general service exception for the service in question.</returns>
         AmazonServiceException UnmarshallException(R input, Exception innerException, HttpStatusCode statusCode);
+
+        /// <summary>
+        /// Given the current position in the stream, extract a T
+        /// </summary>
+        /// <param name="input">The parsing context</param>
+        /// <returns>An object of type T populated with data from the XML stream.</returns>
+        T Unmarshall(R input);
     }
 }
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IErrorResponseUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IXmlErrorResponseUnmarshaller.cs
similarity index 72%
rename from sdk/src/Core/Amazon.Runtime/Internal/Transform/IErrorResponseUnmarshaller.cs
rename to sdk/src/Core/Amazon.Runtime/Internal/Transform/IXmlErrorResponseUnmarshaller.cs
index 1592260b481d..b39973ca38f9 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IErrorResponseUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IXmlErrorResponseUnmarshaller.cs
@@ -29,17 +29,16 @@ namespace Amazon.Runtime.Internal.Transform
     /// in the XML stream goes into what members of an object. 
     /// </summary>
     /// <typeparam name="TUnmarshaller">The type of object the unmarshaller returns</typeparam>
-    /// <typeparam name="TUnmarshalleContext">The type of the XML unmashaller context, which contains the
-    /// state during parsing of the XML stream. Usually an instance of 
-    /// <c>Amazon.Runtime.Internal.Transform.UnmarshallerContext</c>.</typeparam>
-    public interface IErrorResponseUnmarshaller<TUnmarshaller, TUnmarshalleContext> : IUnmarshaller<TUnmarshaller, TUnmarshalleContext>
+    /// <typeparam name="TXmlUnmarshallerContext">The type of the XML unmashaller context, which contains the
+    /// state during parsing of the XML stream.</typeparam>
+    public interface IXmlErrorResponseUnmarshaller<TUnmarshaller, TXmlUnmarshallerContext> : IXmlUnmarshaller<TUnmarshaller, TXmlUnmarshallerContext>
     {
         /// <summary>
         /// Given the current position in the XML stream, extract a T.
         /// </summary>
         /// <param name="input">The XML parsing context</param>
-        /// <param name="errorResponse"></param>
+        /// <param name="errorResponse">The error response</param>
         /// <returns>An object of type T populated with data from the XML stream.</returns>
-        TUnmarshaller Unmarshall(TUnmarshalleContext input, ErrorResponse errorResponse);
+        TUnmarshaller Unmarshall(XmlUnmarshallerContext input, ErrorResponse errorResponse);
     }
 }
\ No newline at end of file
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IXmlUnmarshaller.cs
similarity index 65%
rename from sdk/src/Core/Amazon.Runtime/Internal/Transform/IUnmarshaller.cs
rename to sdk/src/Core/Amazon.Runtime/Internal/Transform/IXmlUnmarshaller.cs
index 7f5e2b95187b..02bce06686cb 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/IUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/IXmlUnmarshaller.cs
@@ -29,16 +29,10 @@ namespace Amazon.Runtime.Internal.Transform
     /// in the XML stream goes into what members of an object. 
     /// </summary>
     /// <typeparam name="T">The type of object the unmarshaller returns</typeparam>
-    /// <typeparam name="R">The type of the XML unmashaller context, which contains the
-    /// state during parsing of the XML stream. Usually an instance of 
-    /// <c>Amazon.Runtime.Internal.Transform.UnmarshallerContext</c>.</typeparam>
-    public interface IUnmarshaller<T, R>
+    /// <typeparam name="TXmlUnmarshallerContext">The type of the XML unmashaller context, which contains the
+    /// state during parsing of the XML stream.</typeparam>
+    public interface IXmlUnmarshaller<T, TXmlUnmarshallerContext>
     {
-        /// <summary>
-        /// Given the current position in the XML stream, extract a T.
-        /// </summary>
-        /// <param name="input">The XML parsing context</param>
-        /// <returns>An object of type T populated with data from the XML stream.</returns>
-        T Unmarshall(R input);
+        T Unmarshall(TXmlUnmarshallerContext input);
     }
 }
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonErrorResponseUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonErrorResponseUnmarshaller.cs
index fbc42fbcf0bf..f6625714d171 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonErrorResponseUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonErrorResponseUnmarshaller.cs
@@ -14,115 +14,129 @@
  */
 
 using Amazon.Runtime.Internal;
+using Amazon.Runtime.Internal.Util;
 using System;
 using Amazon.Util;
 using System.Xml;
-using ThirdParty.Json.LitJson;
 using System.Text;
 using System.IO;
+using System.Text.Json;
 
 namespace Amazon.Runtime.Internal.Transform
 {
     /// <summary>
-    ///    First-pass unmarshaller for all errors
+    /// First-pass unmarshaller for all errors
     /// </summary>
-    public class JsonErrorResponseUnmarshaller : IUnmarshaller<ErrorResponse, JsonUnmarshallerContext>
+    public class JsonErrorResponseUnmarshaller : IJsonUnmarshaller<ErrorResponse, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Build an ErrorResponse from json 
         /// </summary>
         /// <param name="context">The json parsing context. 
+        /// <param name="reader">The Utf8JsonReader</param>
         /// Usually an <c>Amazon.Runtime.Internal.JsonUnmarshallerContext</c>.</param>
         /// <returns>An <c>ErrorResponse</c> object.</returns>
-        public ErrorResponse Unmarshall(JsonUnmarshallerContext context)
+        public ErrorResponse Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             ErrorResponse response;
 
-            if (context.Peek() == 60) //starts with '<' so assuming XML.
+            // we cannot use context.Peek() because the stream used by streamreader has been read to completion by the 
+            // streamingutf8jsonreader. Since responseBody will be populated, we use that instead.
+            for (int i = 0; i < context.ResponseBody.Length; i++)
             {
-                ErrorResponseUnmarshaller xmlUnmarshaller = new ErrorResponseUnmarshaller();
-                using (var stream = new MemoryStream(context.GetResponseBodyBytes()))
-                {
-                    XmlUnmarshallerContext xmlContext = new XmlUnmarshallerContext(stream, false, null);
-                    response = xmlUnmarshaller.Unmarshall(xmlContext);
-                }
-            }
-            else
-            {
-                string type;
-                string message;
-                string code;
-                string requestId = null;
-                GetValuesFromJsonIfPossible(context, out type, out message, out code);
-
-                // If an error code was not found, check for the x-amzn-ErrorType header. 
-                // This header is returned by rest-json services.
-                if (string.IsNullOrEmpty(type) &&
-                    context.ResponseData.IsHeaderPresent(HeaderKeys.XAmzErrorType))
+                if (context.ResponseBody[i] == 32) // skip whitespace
+                    continue;
+                else
                 {
-                    var errorType = context.ResponseData.GetHeaderValue(HeaderKeys.XAmzErrorType);
-                    if (!string.IsNullOrEmpty(errorType))
+                    if (context.ResponseBody[i] == 60) //starts with '<' so assuming XML.
                     {
-                        // The error type can contain additional information, with ":" as a delimiter
-                        // We are only interested in the initial part which is the error type
-                        type = ParseType(errorType);
+                        XmlErrorResponseUnmarshaller xmlUnmarshaller = new XmlErrorResponseUnmarshaller();
+                        using (var stream = new MemoryStream(context.GetResponseBodyBytes()))
+                        {
+                            XmlUnmarshallerContext xmlContext = new XmlUnmarshallerContext(stream, false, null);
+                            response = xmlUnmarshaller.Unmarshall(xmlContext);
+                            return response;
+                        }
                     }
+                    else
+                        break;
                 }
+            }
 
-                // Check for the x-amzn-error-message header. This header is returned by rest-json services.
-                // If the header is present it is preferred over any value provided in the response body.
-                if (context.ResponseData.IsHeaderPresent(HeaderKeys.XAmznErrorMessage))
-                {
-                    var errorMessage = context.ResponseData.GetHeaderValue(HeaderKeys.XAmznErrorMessage);
-                    if (!string.IsNullOrEmpty(errorMessage))
-                        message = errorMessage;
-                }
+            string type;
+            string message;
+            string code;
+            string requestId = null;
+            GetValuesFromJsonIfPossible(context, ref reader, out type, out message, out code);
 
-                // if both "__type" and HeaderKeys.XAmzErrorType were not specified, use "code" as type
-                // this impacts Glacier
-                if (string.IsNullOrEmpty(type) &&
-                    !string.IsNullOrEmpty(code))
+            // If an error code was not found, check for the x-amzn-ErrorType header. 
+            // This header is returned by rest-json services.
+            if (string.IsNullOrEmpty(type) &&
+                context.ResponseData.IsHeaderPresent(HeaderKeys.XAmzErrorType))
+            {
+                var errorType = context.ResponseData.GetHeaderValue(HeaderKeys.XAmzErrorType);
+                if (!string.IsNullOrEmpty(errorType))
                 {
-                    type = code;
+                    // The error type can contain additional information, with ":" as a delimiter
+                    // We are only interested in the initial part which is the error type
+                    type = ParseType(errorType);
                 }
+            }
+
+            // Check for the x-amzn-error-message header. This header is returned by rest-json services.
+            // If the header is present it is preferred over any value provided in the response body.
+            if (context.ResponseData.IsHeaderPresent(HeaderKeys.XAmznErrorMessage))
+            {
+                var errorMessage = context.ResponseData.GetHeaderValue(HeaderKeys.XAmznErrorMessage);
+                if (!string.IsNullOrEmpty(errorMessage))
+                    message = errorMessage;
+            }
+
+            // if both "__type" and HeaderKeys.XAmzErrorType were not specified, use "code" as type
+            // this impacts Glacier
+            if (string.IsNullOrEmpty(type) &&
+                !string.IsNullOrEmpty(code))
+            {
+                type = code;
+            }
 
-                // strip extra data from type, leaving only the exception type name
-                type = type == null ? null : ParseType(type.Substring(type.LastIndexOf("#", StringComparison.Ordinal) + 1));
-                // if no message was found create a generic message
-                if (string.IsNullOrEmpty(message))
+            // strip extra data from type, leaving only the exception type name
+            type = type == null ? null : ParseType(type.Substring(type.LastIndexOf("#", StringComparison.Ordinal) + 1));
+            // if no message was found create a generic message
+            if (string.IsNullOrEmpty(message))
+            {
+                if (string.IsNullOrEmpty(type))
                 {
-                    if (string.IsNullOrEmpty(type))
-                    {
-                        if (string.IsNullOrEmpty(context.ResponseBody))
-                            message = "The service returned an error. See inner exception for details.";
-                        else
-                            message = "The service returned an error with HTTP Body: " + context.ResponseBody;
-                    }
+                    if (string.IsNullOrEmpty(context.ResponseBody))
+                        message = "The service returned an error. See inner exception for details.";
                     else
-                    {
-                        if (string.IsNullOrEmpty(context.ResponseBody))
-                            message = "The service returned an error with Error Code " + type + ".";
-                        else
-                            message = "The service returned an error with Error Code " + type + " and HTTP Body: " + context.ResponseBody;
-                    }
+                        message = "The service returned an error with HTTP Body: " + context.ResponseBody;
                 }
-
-                // Check for the x-amzn-RequestId header. This header is returned by rest-json services.
-                // If the header is present it is preferred over any value provided in the response body.
-                if (context.ResponseData.IsHeaderPresent(HeaderKeys.RequestIdHeader))
+                else
                 {
-                    requestId = context.ResponseData.GetHeaderValue(HeaderKeys.RequestIdHeader);
+                    if (string.IsNullOrEmpty(context.ResponseBody))
+                        message = "The service returned an error with Error Code " + type + ".";
+                    else
+                        message = "The service returned an error with Error Code " + type + " and HTTP Body: " + context.ResponseBody;
                 }
+            }
 
-                response = new ErrorResponse
-                {
-                    Code = type,
-                    Message = message,
-                    // type is not applicable to JSON services, setting to Unknown
-                    Type = ErrorType.Unknown,
-                    RequestId = requestId
-                };
+            // Check for the x-amzn-RequestId header. This header is returned by rest-json services.
+            // If the header is present it is preferred over any value provided in the response body.
+            if (context.ResponseData.IsHeaderPresent(HeaderKeys.RequestIdHeader))
+            {
+                requestId = context.ResponseData.GetHeaderValue(HeaderKeys.RequestIdHeader);
             }
+
+            response = new ErrorResponse
+            {
+                Code = type,
+                Message = message,
+                // type is not applicable to JSON services, setting to Unknown
+                Type = ErrorType.Unknown,
+                RequestId = requestId
+            };
+            
             
             return response;
         }
@@ -140,37 +154,37 @@ private static string ParseType(string type)
 
         }
 
-        private static void GetValuesFromJsonIfPossible(JsonUnmarshallerContext context, out string type, out string message, out string code)
+        private static void GetValuesFromJsonIfPossible(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader,  out string type, out string message, out string code)
         {
             code = null;
             type = null;
             message = null;
 
-            while (TryReadContext(context))
+            while (TryReadContext(context, ref reader))
             {
                 if (context.TestExpression("__type"))
                 {
-                    type = StringUnmarshaller.GetInstance().Unmarshall(context);
+                    type = StringUnmarshaller.GetInstance().Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("message"))
                 {
-                    message = StringUnmarshaller.GetInstance().Unmarshall(context);
+                    message = StringUnmarshaller.GetInstance().Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("code"))
                 {
-                    code = StringUnmarshaller.GetInstance().Unmarshall(context);
+                    code = StringUnmarshaller.GetInstance().Unmarshall(context, ref reader);
                     continue;
                 }
             }
         }
 
-        private static bool TryReadContext(JsonUnmarshallerContext context)
+        private static bool TryReadContext(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             try
             {
-                return context.Read();
+                return context.Read(ref reader);
             }
             catch (JsonException)
             {
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonUnmarshallerContext.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonUnmarshallerContext.cs
index 1f1fda7c4293..b22da8f4d5c0 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonUnmarshallerContext.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/JsonUnmarshallerContext.cs
@@ -19,6 +19,7 @@
 using System.Text;
 using ThirdParty.Json.LitJson;
 using Amazon.Runtime.Internal.Util;
+using System.Text.Json;
 
 namespace Amazon.Runtime.Internal.Transform
 {
@@ -49,9 +50,8 @@ public class JsonUnmarshallerContext : UnmarshallerContext
         #region Private members
 
         private StreamReader streamReader = null;
-        private JsonReader jsonReader = null;
         private JsonPathStack stack = new JsonPathStack();
-        private JsonToken? currentToken = null;
+        private JsonTokenType? currentToken = null;
         private bool disposed = false;
         private bool wasPeeked = false;
         #endregion
@@ -129,17 +129,28 @@ public JsonUnmarshallerContext(
                     base.SetupFlexibleChecksumStream(responseData, CrcStream ?? responseStream, contentLength, requestContext);
                 }
             }
-
+            
             if (this.FlexibleChecksumStream != null) // either just flexible checksum, or flexible checksum wrapping the older CRC stream
                 streamReader = new StreamReader(this.FlexibleChecksumStream);
             else if (this.CrcStream != null)
                 streamReader = new StreamReader(this.CrcStream);
             else
                 streamReader = new StreamReader(responseStream);
-
-            jsonReader = new JsonReader(streamReader);
         }
 
+        #endregion
+        #region Public Methods
+
+        /// <summary>
+        /// Reads the next token at depth greater than or equal to target depth.
+        /// </summary>
+        /// <param name="targetDepth">Tokens are read at depth greater than or equal to target depth.</param>
+        /// <param name="reader">The Utf8JsonReader used to read the document</param>
+        /// <returns>True if a token was read and current depth is greater than or equal to target depth.</returns>
+        public bool ReadAtDepth(int targetDepth, ref StreamingUtf8JsonReader reader)
+        {
+            return Read(ref reader) && this.CurrentDepth >= targetDepth;
+        }
         #endregion
 
         #region Overrides
@@ -151,7 +162,7 @@ public override bool IsStartOfDocument
         {
             get
             {
-                return (CurrentTokenType == JsonToken.None) && (!streamReader.EndOfStream);
+                return (CurrentTokenType == JsonTokenType.None) && (!streamReader.EndOfStream);
             }
         }
 
@@ -160,7 +171,7 @@ public override bool IsStartOfDocument
         /// </summary>    
         public override bool IsEndElement
         {
-            get { return CurrentTokenType == JsonToken.ObjectEnd; }
+            get { return CurrentTokenType == JsonTokenType.EndObject; }
         }
 
         /// <summary>
@@ -168,7 +179,7 @@ public override bool IsEndElement
         /// </summary>
         public override bool IsStartElement
         {
-            get { return CurrentTokenType == JsonToken.ObjectStart; }
+            get { return CurrentTokenType == JsonTokenType.StartObject; }
         }
 
         /// <summary>
@@ -201,7 +212,7 @@ public override string CurrentPath
         /// <returns>
         ///     True if a token was read, false if there are no more tokens to read.
         /// </returns>
-        public override bool Read()
+        public bool Read(ref StreamingUtf8JsonReader reader)
         {
             if (wasPeeked)
             {
@@ -209,11 +220,11 @@ public override bool Read()
                 return currentToken == null;
             }
             
-            bool result = jsonReader.Read();
+            bool result = reader.Read();
             if (result)
             {
-                currentToken = jsonReader.Token;
-                UpdateContext();
+                currentToken = reader.Reader.TokenType;
+                UpdateContext(ref reader);
             }
             else
             {
@@ -231,13 +242,14 @@ public override bool Read()
         /// will return the same data until a Read() call is made.
         /// </summary>
         /// <param name="token">Token to peek.</param>
+        /// <param name="reader">The Utf8JsonReader</param>
         /// <returns>Returns true if the peeked token matches given token.</returns>
-        public bool Peek(JsonToken token)
+        public bool Peek(JsonTokenType token, ref StreamingUtf8JsonReader reader)
         {
             if (wasPeeked)
                 return currentToken != null && currentToken == token;
 
-            if (Read())
+            if (Read(ref reader))
             {
                 wasPeeked = true;
                 return currentToken == token;
@@ -245,46 +257,34 @@ public bool Peek(JsonToken token)
             return false;
         }
 
-        /// <summary>
-        ///     Returns the text contents of the current token being parsed.
-        /// </summary>
-        /// <returns>
-        ///     The text contents of the current token being parsed.
-        /// </returns>
-        public override string ReadText()
+        public string ReadText(ref StreamingUtf8JsonReader reader)
         {
-            object data = jsonReader.Value;
-            string text;
+            string text = string.Empty;
             switch (currentToken)
             {
-                case JsonToken.Null:
+                case JsonTokenType.Null:
                     text = null;
                     break;
-                case JsonToken.String:
-                case JsonToken.PropertyName:
-                    text = data as string;
+                case JsonTokenType.String:
+                    text = reader.Reader.GetString();
+                    break;
+                case JsonTokenType.Number:
+                    if (reader.Reader.TryGetInt64(out long longValue))
+                        text = longValue.ToString(CultureInfo.InvariantCulture);
+                    else if (reader.Reader.TryGetDouble(out double doubleValue))
+                        text = doubleValue.ToString(CultureInfo.InvariantCulture);
+                    else if (reader.Reader.TryGetInt32(out int intValue))
+                        text = intValue.ToString(CultureInfo.InvariantCulture);
                     break;
-                case JsonToken.Boolean:
-                case JsonToken.Int:
-                case JsonToken.UInt:
-                case JsonToken.Long:
-                case JsonToken.ULong:
-                    IFormattable iformattable = data as IFormattable;
-                    if (iformattable != null)
-                        text = iformattable.ToString(null, CultureInfo.InvariantCulture);
-                    else
-                        text = data.ToString();
+                case JsonTokenType.PropertyName:
+                    text = reader.Reader.GetString();
                     break;
-                case JsonToken.Double:
-                    var formattable = data as IFormattable;
-                    if (formattable != null)
-                        text = formattable.ToString("R", CultureInfo.InvariantCulture);
-                    else
-                        text = data.ToString();
+                case JsonTokenType.True:
+                case JsonTokenType.False:
+                    text = reader.Reader.GetBoolean().ToString();
                     break;
                 default:
-                    throw new AmazonClientException(
-                            "We expected a VALUE token but got: " + currentToken);
+                    throw new AmazonClientException($"Unexpected token: {currentToken}");
             }
             return text;
         }
@@ -296,9 +296,9 @@ public override string ReadText()
         /// <summary>
         /// The type of the current token
         /// </summary>
-        public JsonToken CurrentTokenType
+        public JsonTokenType? CurrentTokenType
         {
-            get { return currentToken.Value; }
+            get { return currentToken; }
         }
 
         #endregion
@@ -353,11 +353,11 @@ private int StreamPeek()
             return peek;
         }
 
-        private void UpdateContext()
+        private void UpdateContext(ref StreamingUtf8JsonReader reader)
         {
             if (!currentToken.HasValue) return;
 
-            if (currentToken.Value == JsonToken.ObjectStart || currentToken.Value == JsonToken.ArrayStart)
+            if (currentToken.Value == JsonTokenType.StartObject || currentToken.Value == JsonTokenType.StartArray)
             {
                 // Push '/' for object start and array start.
                 stack.Push(new PathSegment
@@ -366,7 +366,7 @@ private void UpdateContext()
                     Value = DELIMITER
                 });
             }
-            else if (currentToken.Value == JsonToken.ObjectEnd || currentToken.Value == JsonToken.ArrayEnd)
+            else if (currentToken.Value == JsonTokenType.EndObject || currentToken.Value == JsonTokenType.EndArray)
             {
                 if (stack.Peek().SegmentType == PathSegmentType.Delimiter)
                 {
@@ -384,9 +384,9 @@ private void UpdateContext()
             // if the stack is empty and the token type is a string, then the document is a raw string with no opening or
             // closing delimeter. Per smithy spec https://smithy.io/2.0/spec/simple-types.html#document this is allowed
             // so we should just push the value so that it can be retrieved later.
-            else if (currentToken.Value == JsonToken.PropertyName || (stack.Count == 0 && currentToken == JsonToken.String))
+            else if (currentToken.Value == JsonTokenType.PropertyName || (stack.Count == 0 && currentToken == JsonTokenType.String))
             {
-                string t = ReadText();
+                string t = ReadText(ref reader);
 
                 // Push property name, it's appended to the stack's CurrentPath,
                 // it this does not affect the depth.
@@ -396,7 +396,7 @@ private void UpdateContext()
                     Value = t
                 });
             }
-            else if (currentToken.Value != JsonToken.None && stack.Peek().SegmentType != PathSegmentType.Delimiter)
+            else if (currentToken.Value != JsonTokenType.None && stack.Peek().SegmentType != PathSegmentType.Delimiter)
             {
                 // Pop if you encounter a simple data type or null
                 // This will pop the property name associated with it in cases like  {"a":"b"}.
@@ -408,17 +408,6 @@ private void UpdateContext()
         }
 
         #endregion
-
-        public JsonData ToJsonData()
-        {
-            var data = JsonMapper.ToObject(jsonReader);
-
-            if (stack.Count > 0)
-                stack.Pop();
-            
-            return data;
-        }
-
         protected override void Dispose(bool disposing)
         {
             if (!disposed)
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/ResponseUnmarshallers.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/ResponseUnmarshallers.cs
index 0be45973d44e..df1005130ed9 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/ResponseUnmarshallers.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/ResponseUnmarshallers.cs
@@ -22,6 +22,7 @@
 using Amazon.Util;
 using Amazon.Runtime.Internal.Util;
 using System.Globalization;
+using System.Text.Json;
 
 namespace Amazon.Runtime.Internal.Transform
 {
@@ -95,7 +96,7 @@ public AmazonWebServiceResponse UnmarshallResponse(UnmarshallerContext context)
 
         public abstract AmazonWebServiceResponse Unmarshall(UnmarshallerContext input);
 
-#endregion
+        #endregion
 
         public static string GetDefaultErrorMessage<T>() where T : Exception
         {
@@ -154,7 +155,7 @@ public override AmazonServiceException UnmarshallException(UnmarshallerContext i
         }
 
         public abstract AmazonWebServiceResponse Unmarshall(XmlUnmarshallerContext input);
-
+        
         public abstract AmazonServiceException UnmarshallException(XmlUnmarshallerContext input, Exception innerException, HttpStatusCode statusCode);
 
         protected override UnmarshallerContext ConstructUnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData response, bool isException)
@@ -227,19 +228,17 @@ public override AmazonWebServiceResponse Unmarshall(UnmarshallerContext input)
                 throw new AmazonUnmarshallingException(requestId, context.CurrentPath, e, context.ResponseData.StatusCode);
             }
         }
+
         public override AmazonServiceException UnmarshallException(UnmarshallerContext input, Exception innerException, HttpStatusCode statusCode)
         {
             JsonUnmarshallerContext context = input as JsonUnmarshallerContext;
             if (context == null)
                 throw new InvalidOperationException("Unsupported UnmarshallerContext");
-
             var responseException = this.UnmarshallException(context, innerException, statusCode);
             responseException.RequestId = context.ResponseData.GetHeaderValue(HeaderKeys.RequestIdHeader);
             return responseException;
         }
 
-        public abstract AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext input);
-
         public abstract AmazonServiceException UnmarshallException(JsonUnmarshallerContext input, Exception innerException, HttpStatusCode statusCode);
 
         protected override UnmarshallerContext ConstructUnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData response, bool isException)
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/SimpleTypeUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/SimpleTypeUnmarshaller.cs
index 7a75f894fb4f..e4aea164fceb 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/SimpleTypeUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/SimpleTypeUnmarshaller.cs
@@ -17,7 +17,7 @@
 using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
-
+using System.Text.Json;
 using Amazon.Runtime.Internal.Util;
 using Amazon.Util;
 using ThirdParty.Json.LitJson;
@@ -32,10 +32,10 @@ public static T Unmarshall(XmlUnmarshallerContext context)
             return (T)Convert.ChangeType(text, typeof(T), CultureInfo.InvariantCulture);
         }
 
-        public static T Unmarshall(JsonUnmarshallerContext context)
+        public static T Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
             if (text == null)
                 return default(T);
 
@@ -46,7 +46,7 @@ public static T Unmarshall(JsonUnmarshallerContext context)
     /// <summary>
     /// Unmarshaller for int fields
     /// </summary>
-    public class IntUnmarshaller : IUnmarshaller<int, XmlUnmarshallerContext>, IUnmarshaller<int, JsonUnmarshallerContext>
+    public class IntUnmarshaller : IXmlUnmarshaller<int, XmlUnmarshallerContext>, IJsonUnmarshaller<int, JsonUnmarshallerContext>
     {
         private IntUnmarshaller() { }
 
@@ -69,9 +69,9 @@ public int Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<int>.Unmarshall(context);
         }
-        public int Unmarshall(JsonUnmarshallerContext context)
+        public int Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<int>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<int>.Unmarshall(context, ref reader);
         }
     }
 
@@ -81,7 +81,7 @@ public int Unmarshall(JsonUnmarshallerContext context)
     /// This unmarshaller is not implemented for XML context, as XML responses
     /// will null elements (xsi:nil='true') will be skipped by the XML parser.
     /// </summary>
-    public class NullableIntUnmarshaller : IUnmarshaller<int?, XmlUnmarshallerContext>, IUnmarshaller<int?, JsonUnmarshallerContext>
+    public class NullableIntUnmarshaller : IXmlUnmarshaller<int?, XmlUnmarshallerContext>, IJsonUnmarshaller<int?, JsonUnmarshallerContext>
     {   
         private NullableIntUnmarshaller() { }
 
@@ -112,10 +112,10 @@ public static NullableIntUnmarshaller GetInstance()
             return int.Parse(text, CultureInfo.InvariantCulture);
         }
 
-        public int? Unmarshall(JsonUnmarshallerContext context)
+        public int? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
 
             if (text == null)
             {
@@ -128,7 +128,7 @@ public static NullableIntUnmarshaller GetInstance()
     /// <summary>
     /// Unmarshaller for long fields
     /// </summary>
-    public class LongUnmarshaller : IUnmarshaller<long, XmlUnmarshallerContext>, IUnmarshaller<long, JsonUnmarshallerContext>
+    public class LongUnmarshaller : IXmlUnmarshaller<long, XmlUnmarshallerContext>, IJsonUnmarshaller<long, JsonUnmarshallerContext>
     {
         private LongUnmarshaller() { }
 
@@ -151,13 +151,13 @@ public long Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<long>.Unmarshall(context);
         }
-        public long Unmarshall(JsonUnmarshallerContext context)
+        public long Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<long>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<long>.Unmarshall(context, ref reader);
         }
     }
 
-    public class NullableLongUnmarshaller : IUnmarshaller<long?, XmlUnmarshallerContext>, IUnmarshaller<long?, JsonUnmarshallerContext>
+    public class NullableLongUnmarshaller : IXmlUnmarshaller<long?, XmlUnmarshallerContext>, IJsonUnmarshaller<long?, JsonUnmarshallerContext>
     {
         private NullableLongUnmarshaller() { }
 
@@ -183,10 +183,10 @@ public static NullableLongUnmarshaller Instance
             return long.Parse(text, CultureInfo.InvariantCulture);
         }
 
-        public long? Unmarshall(JsonUnmarshallerContext context)
+        public long? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
 
             if (text == null)
             {
@@ -199,7 +199,7 @@ public static NullableLongUnmarshaller Instance
     /// <summary>
     /// Unmarshaller for float fields
     /// </summary>
-    public class FloatUnmarshaller : IUnmarshaller<float, XmlUnmarshallerContext>, IUnmarshaller<float, JsonUnmarshallerContext>
+    public class FloatUnmarshaller : IXmlUnmarshaller<float, XmlUnmarshallerContext>, IJsonUnmarshaller<float, JsonUnmarshallerContext>
     {
         private FloatUnmarshaller() { }
 
@@ -222,16 +222,16 @@ public float Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<float>.Unmarshall(context);
         }
-        public float Unmarshall(JsonUnmarshallerContext context)
+        public float Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<float>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<float>.Unmarshall(context, ref reader);
         }
     }
 
     /// <summary>
     /// Unmarshaller for float fields
     /// </summary>
-    public class NullableFloatUnmarshaller : IUnmarshaller<float?, XmlUnmarshallerContext>, IUnmarshaller<float?, JsonUnmarshallerContext>
+    public class NullableFloatUnmarshaller : IXmlUnmarshaller<float?, XmlUnmarshallerContext>, IJsonUnmarshaller<float?, JsonUnmarshallerContext>
     {
         private NullableFloatUnmarshaller() { }
 
@@ -257,10 +257,10 @@ public static NullableFloatUnmarshaller Instance
             return float.Parse(text, CultureInfo.InvariantCulture);
         }
 
-        public float? Unmarshall(JsonUnmarshallerContext context)
+        public float? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
 
             if (text == null)
             {
@@ -274,7 +274,7 @@ public static NullableFloatUnmarshaller Instance
     /// <summary>
     /// Unmarshaller for double fields
     /// </summary>
-    public class DoubleUnmarshaller : IUnmarshaller<double, XmlUnmarshallerContext>, IUnmarshaller<double, JsonUnmarshallerContext>
+    public class DoubleUnmarshaller : IXmlUnmarshaller<double, XmlUnmarshallerContext>, IJsonUnmarshaller<double, JsonUnmarshallerContext>
     {
         private DoubleUnmarshaller() { }
 
@@ -298,16 +298,16 @@ public double Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<double>.Unmarshall(context);
         }
-        public double Unmarshall(JsonUnmarshallerContext context)
+        public double Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<double>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<double>.Unmarshall(context, ref reader);
         }
     }
 
     /// <summary>
     /// Unmarshaller for double fields
     /// </summary>
-    public class NullableDoubleUnmarshaller : IUnmarshaller<double?, XmlUnmarshallerContext>, IUnmarshaller<double?, JsonUnmarshallerContext>
+    public class NullableDoubleUnmarshaller : IXmlUnmarshaller<double?, XmlUnmarshallerContext>, IJsonUnmarshaller<double?, JsonUnmarshallerContext>
     {
         private NullableDoubleUnmarshaller() { }
 
@@ -333,10 +333,10 @@ public static NullableDoubleUnmarshaller Instance
             return double.Parse(text, CultureInfo.InvariantCulture);
         }
 
-        public double? Unmarshall(JsonUnmarshallerContext context)
+        public double? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
 
             if (text == null)
             {
@@ -349,7 +349,7 @@ public static NullableDoubleUnmarshaller Instance
     /// <summary>
     /// Unmarshaller for decimal fields
     /// </summary>
-    public class DecimalUnmarshaller : IUnmarshaller<decimal, XmlUnmarshallerContext>, IUnmarshaller<decimal, JsonUnmarshallerContext>
+    public class DecimalUnmarshaller : IXmlUnmarshaller<decimal, XmlUnmarshallerContext>, IJsonUnmarshaller<decimal, JsonUnmarshallerContext>
     {
         private DecimalUnmarshaller() { }
 
@@ -372,16 +372,16 @@ public decimal Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<decimal>.Unmarshall(context);
         }
-        public decimal Unmarshall(JsonUnmarshallerContext context)
+        public decimal Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<decimal>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<decimal>.Unmarshall(context, ref reader);
         }
     }
 
     /// <summary>
     /// Unmarshaller for decimal fields
     /// </summary>
-    public class NullableDecimalUnmarshaller : IUnmarshaller<decimal?, XmlUnmarshallerContext>, IUnmarshaller<decimal?, JsonUnmarshallerContext>
+    public class NullableDecimalUnmarshaller : IXmlUnmarshaller<decimal?, XmlUnmarshallerContext>, IJsonUnmarshaller<decimal?, JsonUnmarshallerContext>
     {
         private NullableDecimalUnmarshaller() { }
 
@@ -407,10 +407,10 @@ public static NullableDecimalUnmarshaller Instance
             return decimal.Parse(text, CultureInfo.InvariantCulture);
         }
 
-        public decimal? Unmarshall(JsonUnmarshallerContext context)
+        public decimal? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
 
             if (text == null)
             {
@@ -423,7 +423,7 @@ public static NullableDecimalUnmarshaller Instance
     /// <summary>
     /// Unmarshaller for bool fields
     /// </summary>
-    public class BoolUnmarshaller : IUnmarshaller<bool, XmlUnmarshallerContext>, IUnmarshaller<bool, JsonUnmarshallerContext>
+    public class BoolUnmarshaller : IXmlUnmarshaller<bool, XmlUnmarshallerContext>, IJsonUnmarshaller<bool, JsonUnmarshallerContext>
     {
         private BoolUnmarshaller() { }
 
@@ -446,16 +446,16 @@ public bool Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<bool>.Unmarshall(context);
         }
-        public bool Unmarshall(JsonUnmarshallerContext context)
+        public bool Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<bool>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<bool>.Unmarshall(context, ref reader);
         }
     }
 
     /// <summary>
     /// Unmarshaller for bool fields
     /// </summary>
-    public class NullableBoolUnmarshaller : IUnmarshaller<bool?, XmlUnmarshallerContext>, IUnmarshaller<bool?, JsonUnmarshallerContext>
+    public class NullableBoolUnmarshaller : IXmlUnmarshaller<bool?, XmlUnmarshallerContext>, IJsonUnmarshaller<bool?, JsonUnmarshallerContext>
     {
         private NullableBoolUnmarshaller() { }
 
@@ -481,10 +481,10 @@ public static NullableBoolUnmarshaller Instance
             return bool.Parse(text);
         }
 
-        public bool? Unmarshall(JsonUnmarshallerContext context)
+        public bool? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
             if(string.IsNullOrEmpty(text))
             {
                 return null;
@@ -497,7 +497,7 @@ public static NullableBoolUnmarshaller Instance
     /// <summary>
     /// Unmarshaller for string fields
     /// </summary>
-    public class StringUnmarshaller : IUnmarshaller<string, XmlUnmarshallerContext>, IUnmarshaller<string, JsonUnmarshallerContext>
+    public class StringUnmarshaller : IXmlUnmarshaller<string, XmlUnmarshallerContext>, IJsonUnmarshaller<string, JsonUnmarshallerContext>
     {
         private StringUnmarshaller() { }
 
@@ -520,16 +520,16 @@ public string Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<string>.Unmarshall(context);
         }
-        public string Unmarshall(JsonUnmarshallerContext context)
+        public string Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<string>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<string>.Unmarshall(context, ref reader);
         }
     }
 
     /// <summary>
     /// Unmarshaller for byte fields
     /// </summary>
-    public class ByteUnmarshaller : IUnmarshaller<byte, XmlUnmarshallerContext>, IUnmarshaller<byte, JsonUnmarshallerContext>
+    public class ByteUnmarshaller : IXmlUnmarshaller<byte, XmlUnmarshallerContext>, IJsonUnmarshaller<byte, JsonUnmarshallerContext>
     {
         private ByteUnmarshaller() { }
 
@@ -552,16 +552,16 @@ public byte Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<byte>.Unmarshall(context);
         }
-        public byte Unmarshall(JsonUnmarshallerContext context)
+        public byte Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return SimpleTypeUnmarshaller<byte>.Unmarshall(context);
+            return SimpleTypeUnmarshaller<byte>.Unmarshall(context, ref reader);
         }
     }
 
     /// <summary>
     /// Unmarshaller for DateTime fields
     /// </summary>
-    public class DateTimeUnmarshaller : IUnmarshaller<DateTime, XmlUnmarshallerContext>, IUnmarshaller<DateTime, JsonUnmarshallerContext>
+    public class DateTimeUnmarshaller : IXmlUnmarshaller<DateTime, XmlUnmarshallerContext>, IJsonUnmarshaller<DateTime, JsonUnmarshallerContext>
     {
         private DateTimeUnmarshaller() { }
 
@@ -586,10 +586,10 @@ public DateTime Unmarshall(XmlUnmarshallerContext context)
             return UnmarshallInternal(text, treatAsNullable: false).Value;
         }
 
-        public DateTime Unmarshall(JsonUnmarshallerContext context)
+        public DateTime Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
             return UnmarshallInternal(text, treatAsNullable: false).Value;
         }
 
@@ -627,7 +627,7 @@ public DateTime Unmarshall(JsonUnmarshallerContext context)
     /// This unmarshaller is not implemented for XML context, as XML responses
     /// will null elements (xsi:nil='true') will be skipped by the XML parser.
     /// </summary>
-    public class NullableDateTimeUnmarshaller : IUnmarshaller<DateTime?, XmlUnmarshallerContext>, IUnmarshaller<DateTime?, JsonUnmarshallerContext>
+    public class NullableDateTimeUnmarshaller : IXmlUnmarshaller<DateTime?, XmlUnmarshallerContext>, IJsonUnmarshaller<DateTime?, JsonUnmarshallerContext>
     {
         private NullableDateTimeUnmarshaller() { }
 
@@ -652,15 +652,15 @@ public static NullableDateTimeUnmarshaller GetInstance()
             return DateTimeUnmarshaller.UnmarshallInternal(text, treatAsNullable: true);
         }
 
-        public DateTime? Unmarshall(JsonUnmarshallerContext context)
+        public DateTime? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
             return DateTimeUnmarshaller.UnmarshallInternal(text, treatAsNullable: true);
         }
     }
 
-    public class DateTimeEpochLongMillisecondsUnmarshaller : IUnmarshaller<DateTime, XmlUnmarshallerContext>, IUnmarshaller<DateTime, JsonUnmarshallerContext>
+    public class DateTimeEpochLongMillisecondsUnmarshaller : IXmlUnmarshaller<DateTime, XmlUnmarshallerContext>, IJsonUnmarshaller<DateTime, JsonUnmarshallerContext>
     {
         private DateTimeEpochLongMillisecondsUnmarshaller() { }
 
@@ -683,15 +683,15 @@ public DateTime Unmarshall(XmlUnmarshallerContext context)
         {
             return SimpleTypeUnmarshaller<DateTime>.Unmarshall(context);
         }
-        public DateTime Unmarshall(JsonUnmarshallerContext context)
+        public DateTime Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            long millseconds = LongUnmarshaller.Instance.Unmarshall(context);
+            long millseconds = LongUnmarshaller.Instance.Unmarshall(context, ref reader);
             var ret = Amazon.Util.AWSSDKUtils.EPOCH_START.AddMilliseconds(millseconds);
             return ret;
         }
     }
 
-    public class NullableDateTimeEpochLongMillisecondsUnmarshaller : IUnmarshaller<DateTime?, XmlUnmarshallerContext>, IUnmarshaller<DateTime?, JsonUnmarshallerContext>
+    public class NullableDateTimeEpochLongMillisecondsUnmarshaller : IXmlUnmarshaller<DateTime?, XmlUnmarshallerContext>, IJsonUnmarshaller<DateTime?, JsonUnmarshallerContext>
     {
         private NullableDateTimeEpochLongMillisecondsUnmarshaller() { }
 
@@ -720,10 +720,10 @@ public static NullableDateTimeEpochLongMillisecondsUnmarshaller Instance
             return ret;
         }
 
-        public DateTime? Unmarshall(JsonUnmarshallerContext context)
+        public DateTime? Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            string text = context.ReadText();
+            context.Read(ref reader);
+            string text = context.ReadText(ref reader);
 
             if (text == null)
             {
@@ -739,7 +739,7 @@ public static NullableDateTimeEpochLongMillisecondsUnmarshaller Instance
     /// <summary>
     /// Unmarshaller for MemoryStream fields
     /// </summary>
-    public class MemoryStreamUnmarshaller : IUnmarshaller<MemoryStream, XmlUnmarshallerContext>, IUnmarshaller<MemoryStream, JsonUnmarshallerContext>
+    public class MemoryStreamUnmarshaller : IXmlUnmarshaller<MemoryStream, XmlUnmarshallerContext>, IJsonUnmarshaller<MemoryStream, JsonUnmarshallerContext>
     {
         private MemoryStreamUnmarshaller() { }
 
@@ -765,13 +765,13 @@ public MemoryStream Unmarshall(XmlUnmarshallerContext context)
             return stream;
         }
 
-        public MemoryStream Unmarshall(JsonUnmarshallerContext context)
+        public MemoryStream Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null)
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null)
                 return null;
 
-            byte[] bytes = Convert.FromBase64String(context.ReadText());
+            byte[] bytes = Convert.FromBase64String(context.ReadText(ref reader));
             MemoryStream stream = new MemoryStream(bytes, 0, bytes.Length, true, true);
             return stream;
         }
@@ -780,7 +780,7 @@ public MemoryStream Unmarshall(JsonUnmarshallerContext context)
     /// <summary>
     /// Unmarshaller for ResponseMetadata
     /// </summary>
-    public class ResponseMetadataUnmarshaller : IUnmarshaller<ResponseMetadata, XmlUnmarshallerContext>, IUnmarshaller<ResponseMetadata, JsonUnmarshallerContext>
+    public class ResponseMetadataUnmarshaller : IXmlUnmarshaller<ResponseMetadata, XmlUnmarshallerContext>, IJsonUnmarshaller<ResponseMetadata, JsonUnmarshallerContext>
     {
         private ResponseMetadataUnmarshaller() { }
 
@@ -819,17 +819,17 @@ public ResponseMetadata Unmarshall(XmlUnmarshallerContext context)
 
             return metadata;
         }
-        public ResponseMetadata Unmarshall(JsonUnmarshallerContext context)
+        public ResponseMetadata Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             ResponseMetadata metadata = new ResponseMetadata();
             int depth = context.CurrentDepth;
 
             while (context.CurrentDepth >= depth)
             {
-                context.Read();
+                context.Read(ref reader);
                 if (context.TestExpression("ResponseMetadata/RequestId"))
                 {
-                    metadata.RequestId = StringUnmarshaller.GetInstance().Unmarshall(context);
+                    metadata.RequestId = StringUnmarshaller.GetInstance().Unmarshall(context, ref reader);
                 }
             }
 
@@ -837,16 +837,15 @@ public ResponseMetadata Unmarshall(JsonUnmarshallerContext context)
         }
     }
 
-    public class KeyValueUnmarshaller<K, V, KUnmarshaller, VUnmarshaller> :
-    IUnmarshaller<KeyValuePair<K, V>, XmlUnmarshallerContext>, 
-    IUnmarshaller<KeyValuePair<K, V>, JsonUnmarshallerContext>
-        where KUnmarshaller : IUnmarshaller<K, XmlUnmarshallerContext>, IUnmarshaller<K, JsonUnmarshallerContext>
-        where VUnmarshaller : IUnmarshaller<V, XmlUnmarshallerContext>, IUnmarshaller<V, JsonUnmarshallerContext>
+    public class XmlKeyValueUnmarshaller<K, V, KUnmarshaller, VUnmarshaller> :
+    IXmlUnmarshaller<KeyValuePair<K, V>, XmlUnmarshallerContext>
+        where KUnmarshaller : IXmlUnmarshaller<K, XmlUnmarshallerContext>
+        where VUnmarshaller : IXmlUnmarshaller<V, XmlUnmarshallerContext>
     {
         private KUnmarshaller keyUnmarshaller;
         private VUnmarshaller valueUnmarshaller;
 
-        public KeyValueUnmarshaller(KUnmarshaller keyUnmarshaller, VUnmarshaller valueUnmarshaller)
+        public XmlKeyValueUnmarshaller(KUnmarshaller keyUnmarshaller, VUnmarshaller valueUnmarshaller)
         {
             this.keyUnmarshaller = keyUnmarshaller;
             this.valueUnmarshaller = valueUnmarshaller;
@@ -883,31 +882,47 @@ public KeyValuePair<K, V> Unmarshall(XmlUnmarshallerContext context)
             return new KeyValuePair<K, V>(key, value);
         }
 
-        public KeyValuePair<K, V> Unmarshall(JsonUnmarshallerContext context)
+    }
+
+    public class JsonKeyValueUnmarshaller<K, V, KUnmarshaller, VUnmarshaller> :
+        IJsonUnmarshaller<KeyValuePair<K, V>, JsonUnmarshallerContext>
+        where KUnmarshaller : IJsonUnmarshaller<K, JsonUnmarshallerContext>
+        where VUnmarshaller : IJsonUnmarshaller<V, JsonUnmarshallerContext>
+    {
+        private KUnmarshaller keyUnmarshaller;
+        private VUnmarshaller valueUnmarshaller;
+
+        public JsonKeyValueUnmarshaller(KUnmarshaller keyUnmarshaller, VUnmarshaller valueUnmarshaller)
         {
-            K key = this.keyUnmarshaller.Unmarshall(context);
-            V value = this.valueUnmarshaller.Unmarshall(context);
+            this.keyUnmarshaller = keyUnmarshaller;
+            this.valueUnmarshaller = valueUnmarshaller;
+        }
+
+        public KeyValuePair<K, V> Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
+        {
+            K key = this.keyUnmarshaller.Unmarshall(context, ref reader);
+            V value = this.valueUnmarshaller.Unmarshall(context, ref reader);
 
             return new KeyValuePair<K, V>(key, value);
         }
     }
 
-    public class ListUnmarshaller<I, IUnmarshaller> : IUnmarshaller<List<I>, XmlUnmarshallerContext>, IUnmarshaller<List<I>, JsonUnmarshallerContext>
-        where IUnmarshaller : IUnmarshaller<I, XmlUnmarshallerContext>, IUnmarshaller<I, JsonUnmarshallerContext>
+    public class XmlListUnmarshaller<T, TUnmarshaller> : IXmlUnmarshaller<List<T>, XmlUnmarshallerContext>
+        where TUnmarshaller : IXmlUnmarshaller<T, XmlUnmarshallerContext>
     {
-        private IUnmarshaller iUnmarshaller;
+        private TUnmarshaller iUnmarshaller;
 
-        public ListUnmarshaller(IUnmarshaller iUnmarshaller)
+        public XmlListUnmarshaller(TUnmarshaller iUnmarshaller)
         {
             this.iUnmarshaller = iUnmarshaller;
         }
-        
-        public List<I> Unmarshall(XmlUnmarshallerContext context)
+
+        public List<T> Unmarshall(XmlUnmarshallerContext context)
         {
             int originalDepth = context.CurrentDepth;
             int targetDepth = originalDepth + 1;
 
-            var list = new List<I>();
+            var list = new List<T>();
             // If the list is nested, we don't want the current depth to be less than the original depth
             // because then, context.Read() will return true if there are more elements and all the
             // list's elements will be unmarshalled as one list instead of multiple nested lists.
@@ -924,40 +939,52 @@ public List<I> Unmarshall(XmlUnmarshallerContext context)
             }
             return list;
         }
-        public List<I> Unmarshall(JsonUnmarshallerContext context)
+    }
+
+    public class JsonListUnmarshaller<T, TUnmarshaller> : IJsonUnmarshaller<List<T>, JsonUnmarshallerContext>
+        where TUnmarshaller : IJsonUnmarshaller<T, JsonUnmarshallerContext>
+    {
+        private TUnmarshaller iUnmarshaller;
+
+        public JsonListUnmarshaller(TUnmarshaller iUnmarshaller)
+        {
+            this.iUnmarshaller = iUnmarshaller;
+        }
+
+        public List<T> Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read(); // Read [ or null
-            if (context.CurrentTokenType == JsonToken.Null)
+            context.Read(ref reader); // Read [ or null
+            if (context.CurrentTokenType == JsonTokenType.Null)
             {
                 if (AWSConfigs.InitializeCollections)
-                    return new List<I>();
+                    return new List<T>();
                 else
                     return null;
             }
 
-
             // If a list is present in the response, use AlwaysSendList,
             // so if the response was empty, reusing the object in the request we will
             // end up sending the same empty collection back.
-            List<I> list = new AlwaysSendList<I>();
-            while (!context.Peek(JsonToken.ArrayEnd)) // Peek for ]
+            List<T> list = new AlwaysSendList<T>();
+            while (!context.Peek(JsonTokenType.EndArray, ref reader)) // Peek for ]
             {
-                list.Add(iUnmarshaller.Unmarshall(context));
+                list.Add(iUnmarshaller.Unmarshall(context, ref reader));
             }
-            context.Read(); // Read ]
+            context.Read(ref reader); // Read ]
             return list;
         }
     }
 
-    public class DictionaryUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller> : IUnmarshaller<Dictionary<TKey, TValue>, XmlUnmarshallerContext>, IUnmarshaller<Dictionary<TKey, TValue>, JsonUnmarshallerContext>
-        where TKeyUnmarshaller : IUnmarshaller<TKey, XmlUnmarshallerContext>, IUnmarshaller<TKey, JsonUnmarshallerContext>
-        where TValueUnmarshaller : IUnmarshaller<TValue, XmlUnmarshallerContext>, IUnmarshaller<TValue, JsonUnmarshallerContext>
+
+    public class XmlDictionaryUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller> : IXmlUnmarshaller<Dictionary<TKey, TValue>, XmlUnmarshallerContext>
+        where TKeyUnmarshaller : IXmlUnmarshaller<TKey, XmlUnmarshallerContext>
+        where TValueUnmarshaller : IXmlUnmarshaller<TValue, XmlUnmarshallerContext>
     {
-        private KeyValueUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller> KVUnmarshaller;
+        private XmlKeyValueUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller> KVUnmarshaller;
 
-        public DictionaryUnmarshaller(TKeyUnmarshaller kUnmarshaller, TValueUnmarshaller vUnmarshaller)
+        public XmlDictionaryUnmarshaller(TKeyUnmarshaller kUnmarshaller, TValueUnmarshaller vUnmarshaller)
         {
-            KVUnmarshaller = new KeyValueUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller>(kUnmarshaller, vUnmarshaller);
+            KVUnmarshaller = new XmlKeyValueUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller>(kUnmarshaller, vUnmarshaller);
         }                
 
         public Dictionary<TKey, TValue> Unmarshall(XmlUnmarshallerContext context)
@@ -983,11 +1010,23 @@ public Dictionary<TKey, TValue> Unmarshall(XmlUnmarshallerContext context)
             
             return dictionary;
         }
+    }
+
+    public class JsonDictionaryUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller> : IJsonUnmarshaller<Dictionary<TKey, TValue>, JsonUnmarshallerContext>
+        where TKeyUnmarshaller :IJsonUnmarshaller<TKey, JsonUnmarshallerContext>
+        where TValueUnmarshaller : IJsonUnmarshaller<TValue, JsonUnmarshallerContext>
+    {
+        private JsonKeyValueUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller> KVUnmarshaller;
+
+        public JsonDictionaryUnmarshaller(TKeyUnmarshaller kUnmarshaller, TValueUnmarshaller vUnmarshaller)
+        {
+            KVUnmarshaller = new JsonKeyValueUnmarshaller<TKey, TValue, TKeyUnmarshaller, TValueUnmarshaller>(kUnmarshaller, vUnmarshaller);
+        }
 
-        public Dictionary<TKey, TValue> Unmarshall(JsonUnmarshallerContext context)
+        public Dictionary<TKey, TValue> Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            context.Read(); // Read { or null
-            if (context.CurrentTokenType == JsonToken.Null)
+            context.Read(ref reader); // Read { or null
+            if (context.CurrentTokenType == JsonTokenType.Null)
             {
                 if (AWSConfigs.InitializeCollections)
                     return new Dictionary<TKey, TValue>();
@@ -1000,12 +1039,12 @@ public Dictionary<TKey, TValue> Unmarshall(JsonUnmarshallerContext context)
             // so if the response was empty, reusing the object in the request we will
             // end up sending the same empty collection back.
             Dictionary<TKey, TValue> dictionary = new AlwaysSendDictionary<TKey, TValue>();
-            while (!context.Peek(JsonToken.ObjectEnd)) // Peek }
+            while (!context.Peek(JsonTokenType.EndObject, ref reader)) // Peek }
             {
-                KeyValuePair<TKey, TValue> item = KVUnmarshaller.Unmarshall(context);
+                KeyValuePair<TKey, TValue> item = KVUnmarshaller.Unmarshall(context, ref reader);
                 dictionary.Add(item.Key, item.Value);
             }
-            context.Read(); // Read }
+            context.Read(ref reader); // Read }
             return dictionary;
 
         }
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/UnmarshallerContext.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/UnmarshallerContext.cs
index 086faa6f2074..dacafbce1f9f 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/UnmarshallerContext.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/UnmarshallerContext.cs
@@ -21,6 +21,7 @@
 using System.IO;
 using System.Xml;
 using ThirdParty.Ionic.Zlib;
+using System.Text.Json;
 
 namespace Amazon.Runtime.Internal.Transform
 {
@@ -184,16 +185,6 @@ public bool TestExpression(string expression, int startingStackDepth)
             return TestExpression(expression, startingStackDepth, CurrentPath, CurrentDepth);
         }
 
-        /// <summary>
-        /// Reads the next token at depth greater than or equal to target depth.
-        /// </summary>
-        /// <param name="targetDepth">Tokens are read at depth greater than or equal to target depth.</param>
-        /// <returns>True if a token was read and current depth is greater than or equal to target depth.</returns>
-        public bool ReadAtDepth(int targetDepth)
-        {
-            return Read() && this.CurrentDepth >= targetDepth;
-        }
-
         private static bool TestExpression(string expression, string currentPath)
         {
             if (expression.Equals("."))
@@ -235,22 +226,6 @@ private static bool TestExpression(string expression, int startingStackDepth, st
         /// </summary>
         public abstract int CurrentDepth { get; }
 
-        /// <summary>
-        /// Reads to the next node in the document, and updates the context accordingly.
-        /// </summary>
-        /// <returns>
-        /// True if a node was read, false if there are no more elements to read.
-        /// </returns>
-        public abstract bool Read();
-
-        /// <summary>
-        ///     Returns the text contents of the current element being parsed.
-        /// </summary>
-        /// <returns>
-        ///     The text contents of the current element being parsed.
-        /// </returns>
-        public abstract string ReadText();
-
         /// <summary>
         /// True if <c>NodeType</c> is <c>Element</c>.
         /// </summary>
@@ -307,404 +282,4 @@ public void Dispose()
 
         #endregion
     }
-
-    /// <summary>
-    /// Wrap an <c>XmltextReader</c> for simulating an event stream.
-    /// 
-    /// Each <c>Read()</c> operation goes either to the next element or next attribute within
-    /// the current element. <c>TestExpression()</c> is used to match the current event
-    /// to an xpath expression. The general pattern looks like this:
-    /// <code>
-    /// UnmarshallerContext context = new UnmarshallerContext(...);
-    /// while (context.Read())
-    /// {
-    ///     if (context.TestExpresion("path/to/element"))
-    ///     {
-    ///         myObject.stringMember = stringUnmarshaller.GetInstance().Unmarshall(context);
-    ///         continue;
-    ///     }
-    ///     if (context.TestExpression("path/to/@attribute"))
-    ///         myObject.MyComplexTypeMember = MyComplexTypeUnmarshaller.GetInstance().Unmarshall(context);
-    /// }
-    /// </code>
-    /// </summary>
-    public class XmlUnmarshallerContext : UnmarshallerContext
-    {
-        #region Private members
-
-        private static HashSet<XmlNodeType> nodesToSkip = new HashSet<XmlNodeType>
-        {
-            XmlNodeType.None,
-            XmlNodeType.XmlDeclaration,
-            XmlNodeType.Comment,
-            XmlNodeType.DocumentType,
-            XmlNodeType.CDATA,
-            XmlNodeType.Whitespace
-        };
-
-        private StreamReader streamReader;
-        private XmlTextReader _xmlTextReader;
-        private Stack<string> stack = new Stack<string>();
-        private string stackString = "";
-        private Dictionary<string, string> attributeValues;
-        private List<string> attributeNames;
-        private IEnumerator<string> attributeEnumerator;
-        private XmlNodeType nodeType;
-        private string nodeContent = String.Empty;
-        private bool disposed = false;
-        private bool currentlyProcessingEmptyElement;
-
-        public Stream Stream
-        {
-            get
-            {
-                return streamReader.BaseStream;
-            }
-        }
-
-        /// <remarks>
-        /// Despite Microsoft's recommendation to use XmlReader for .NET Framework 2.0 or greater 
-        /// (https://docs.microsoft.com/en-us/dotnet/api/system.xml.xmltextreader#remarks), this class
-        /// intentionally uses XmlTextReader to handle the XML related object key constraints 
-        /// for S3 (https://docs.aws.amazon.com/AmazonS3/latest/userguide/object-keys.html).
-        /// </remarks>
-        private XmlTextReader XmlReader
-        {
-            get
-            {
-                if (_xmlTextReader == null)
-                {
-                    _xmlTextReader = new XmlTextReader(streamReader);
-                    _xmlTextReader.WhitespaceHandling = WhitespaceHandling.All;
-                    _xmlTextReader.DtdProcessing = DtdProcessing.Ignore;
-                }
-                return _xmlTextReader;
-            }
-        }
-
-        #endregion
-
-        #region Constructors
-
-        /// <summary>
-        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
-        /// </summary>
-        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
-        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
-        /// <param name="responseData">Response data coming back from the request</param>
-        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
-        public XmlUnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException = false)
-            : this(responseStream, maintainResponseBody, responseData, isException, null)
-        {
-        }
-
-        /// <summary>
-        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
-        /// </summary>
-        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
-        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
-        /// <param name="responseData">Response data coming back from the request</param>
-        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
-        /// <param name="requestContext">Context for the request that produced this response</param>
-        public XmlUnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException, IRequestContext requestContext)
-        {
-            if (isException)
-            {
-                this.WrappingStream = new CachingWrapperStream(responseStream);
-            }
-            else if (maintainResponseBody)
-            {
-                this.WrappingStream = new CachingWrapperStream(responseStream, AWSConfigs.LoggingConfig.LogResponsesSizeLimit);
-            }
-
-            if (isException || maintainResponseBody)
-            {
-                responseStream = this.WrappingStream;
-            }
-            // If the unmarshaller context is being called internally without there being a http response then the response data would be null
-            if (responseData != null)
-            {
-                long contentLength;
-                bool parsedContentLengthHeader = long.TryParse(responseData.GetHeaderValue("Content-Length"), out contentLength);
-
-                if (parsedContentLengthHeader && contentLength == 0)
-                {
-                    IsEmptyResponse = true;
-                }
-                // Validate flexible checksums if we know the content length and the behavior was opted in to on the request
-                if (parsedContentLengthHeader && responseData.ContentLength == contentLength &&
-                        string.IsNullOrEmpty(responseData.GetHeaderValue("Content-Encoding")) &&
-                        requestContext?.OriginalRequest?.CoreChecksumMode == CoreChecksumResponseBehavior.ENABLED)
-                {
-                    SetupFlexibleChecksumStream(responseData, responseStream, contentLength, requestContext);
-                }
-            }
-
-            streamReader = new StreamReader(this.FlexibleChecksumStream ?? responseStream);
-
-            this.WebResponseData = responseData;
-            this.MaintainResponseBody = maintainResponseBody;
-            this.IsException = isException;
-        }
-
-        #endregion
-
-        #region Overrides
-
-        /// <summary>
-        /// The current XML path that is being unmarshalled.
-        /// </summary>
-        public override string CurrentPath
-        {
-            get { return this.stackString; }
-        }
-
-        /// <summary>
-        ///     Returns the element depth of the parser's current position in the XML
-        ///     document being parsed.
-        /// </summary>
-        public override int CurrentDepth
-        {
-            get { return stack.Count; }
-        }
-
-        /// <summary>
-        /// Reads to the next node in the XML document, and updates the context accordingly.
-        /// </summary>
-        /// <returns>
-        /// True if a node was read, false if there are no more elements to read./
-        /// </returns>
-        public override bool Read()
-        {
-            if (attributeEnumerator != null && attributeEnumerator.MoveNext())
-            {
-                this.nodeType = XmlNodeType.Attribute;
-                stackString = string.Format(CultureInfo.InvariantCulture, "{0}/@{1}", StackToPath(stack), attributeEnumerator.Current);
-            }
-            else
-            {
-                // Skip some nodes
-                if (nodesToSkip.Contains(XmlReader.NodeType))
-                    XmlReader.Read();
-
-                if (currentlyProcessingEmptyElement)
-                {
-                    nodeType = XmlNodeType.EndElement;
-                    stack.Pop();
-                    stackString = StackToPath(stack);
-                    XmlReader.Read();
-                    currentlyProcessingEmptyElement = false;
-                }
-                else if(XmlReader.IsEmptyElement)
-                {
-                    //This is a shorthand form of an empty element <element /> and we want to allow it
-                    nodeType = XmlNodeType.Element;
-                    stack.Push(XmlReader.LocalName);
-                    stackString = StackToPath(stack);
-                    currentlyProcessingEmptyElement = true;
-                    nodeContent = String.Empty;
-
-                    //Defer reading so that on next pass we can treat this same element as the end element.
-                }
-                else
-                {
-                    switch (XmlReader.NodeType)
-                    {
-                        case XmlNodeType.EndElement:
-                            this.nodeType = XmlNodeType.EndElement;
-                            stack.Pop();
-                            stackString = StackToPath(stack);
-                            XmlReader.Read();
-                            break;
-                        case XmlNodeType.Element:
-                            nodeType = XmlNodeType.Element;
-                            stack.Push(XmlReader.LocalName);
-                            stackString = StackToPath(stack);
-                            this.ReadElement();
-                            break;
-                    }
-                }
-            }
-
-            bool moreDataAvailable = 
-                XmlReader.ReadState != ReadState.EndOfFile && 
-                XmlReader.ReadState != ReadState.Error &&
-                XmlReader.ReadState != ReadState.Closed;
-            return moreDataAvailable;
-        }
-
-        /// <summary>
-        ///     Returns the text contents of the current element being parsed.
-        /// </summary>
-        /// <returns>
-        ///     The text contents of the current element being parsed.
-        /// </returns>
-        public override string  ReadText()
-        {
-            if (this.nodeType == XmlNodeType.Attribute)
-            {
-                return (attributeValues[attributeEnumerator.Current]);
-            }
-            else
-            {
-                return nodeContent;
-            }
-        }
-
-        /// <summary>
-        /// True if <c>NodeType</c> is <c>Element</c>.
-        /// </summary>
-        public override bool IsStartElement
-        {
-            get { return this.nodeType == XmlNodeType.Element; }
-        }
-
-        /// <summary>
-        /// True if <c>NodeType</c> is <c>EndElement</c>.
-        /// </summary>
-        public override bool IsEndElement
-        {
-            get { return this.nodeType == XmlNodeType.EndElement; }
-        }
-
-        /// <summary>
-        /// True if the context is at the start of the document.
-        /// </summary>
-        public override bool IsStartOfDocument
-        {
-            get { return XmlReader.ReadState == ReadState.Initial; }
-        }
-
-        #endregion
-
-        #region Public methods
-
-        /// <summary>
-        /// True if <c>NodeType</c> is <c>Attribute</c>.
-        /// </summary>
-        public bool IsAttribute
-        {
-            get { return this.nodeType == XmlNodeType.Attribute; }
-        }
-
-        #endregion
-
-        #region Private Methods
-
-        private static string StackToPath(Stack<string> stack)
-        {
-            string path = null;
-            foreach (string s in stack.ToArray())
-            {
-                path = null == path ? s : string.Format(CultureInfo.InvariantCulture, "{0}/{1}", s, path);
-            }
-            return "/" + path;
-        }
-
-        // Move to the next element, cache the attributes collection
-        // and attempt to cache the inner text of the element if applicable.
-        private void ReadElement()
-        {
-            if (XmlReader.HasAttributes)
-            {
-                attributeValues = new Dictionary<string, string>();
-                attributeNames = new List<string>();
-                while (XmlReader.MoveToNextAttribute())
-                {
-                    attributeValues.Add(XmlReader.LocalName, XmlReader.Value);
-                    attributeNames.Add(XmlReader.LocalName);
-                }
-                attributeEnumerator = attributeNames.GetEnumerator();
-            }
-            XmlReader.MoveToElement();
-            XmlReader.Read();
-
-            if (XmlReader.NodeType == XmlNodeType.Text || XmlReader.NodeType == XmlNodeType.Whitespace)
-                nodeContent = XmlReader.ReadContentAsString();
-            else
-                nodeContent = String.Empty;
-        }
-
-        #endregion
-
-        protected override void Dispose(bool disposing)
-        {
-            if (!this.disposed)
-            {
-                if (disposing)
-                {
-                    if (streamReader != null)
-                    {
-                        streamReader.Dispose();
-                        streamReader = null;
-                    }
-                    if (_xmlTextReader != null)
-                    {
-#if NETSTANDARD
-                        _xmlTextReader.Dispose();
-#else
-                        _xmlTextReader.Close();
-#endif
-                        _xmlTextReader = null;
-                    }
-                }
-                disposed = true;
-            }
-            base.Dispose(disposing);
-        }
-    }
-
-    public class EC2UnmarshallerContext : XmlUnmarshallerContext
-    {
-        /// <summary>
-        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
-        /// </summary>
-        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
-        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
-        /// <param name="responseData">Response data coming back from the request</param>
-        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
-        public EC2UnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException = false)
-            : base(responseStream, maintainResponseBody, responseData, isException)
-        {
-        }
-
-        /// <summary>
-        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
-        /// </summary>
-        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
-        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
-        /// <param name="responseData">Response data coming back from the request</param>
-        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
-        /// <param name="requestContext">Context for the request that produced this response</param>
-        public EC2UnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException, IRequestContext requestContext)
-            : base(responseStream, maintainResponseBody, responseData, isException, requestContext)
-        {
-        }
-
-        /// <summary>
-        /// RequestId value, if found in response
-        /// </summary>
-        public string RequestId { get; private set; }
-
-        /// <summary>
-        /// Reads to the next node in the XML document, and updates the context accordingly.
-        /// If node is RequestId, reads the contents and stores in RequestId property.
-        /// </summary>
-        /// <returns>
-        /// True if a node was read, false if there are no more elements to read./
-        /// </returns>
-        public override bool Read()
-        {
-            bool result = base.Read();
-            if (RequestId == null)
-            {
-                if (IsStartElement && TestExpression("RequestId", 2))
-                {
-                    RequestId = StringUnmarshaller.GetInstance().Unmarshall(this);
-                }
-            }
-            return result;
-        }
-    }
-
 }
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/ErrorResponseUnmarshaller.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/XmlErrorResponseUnmarshaller.cs
similarity index 90%
rename from sdk/src/Core/Amazon.Runtime/Internal/Transform/ErrorResponseUnmarshaller.cs
rename to sdk/src/Core/Amazon.Runtime/Internal/Transform/XmlErrorResponseUnmarshaller.cs
index 24c99ec6fd15..6af0180ee1c2 100644
--- a/sdk/src/Core/Amazon.Runtime/Internal/Transform/ErrorResponseUnmarshaller.cs
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/XmlErrorResponseUnmarshaller.cs
@@ -23,7 +23,7 @@ namespace Amazon.Runtime.Internal.Transform
     /// <summary>
     ///    Response Unmarshaller for all Errors
     /// </summary>
-    public class ErrorResponseUnmarshaller : IUnmarshaller<ErrorResponse, XmlUnmarshallerContext>
+    public class XmlErrorResponseUnmarshaller : IXmlUnmarshaller<ErrorResponse, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Build an ErrorResponse from XML 
@@ -108,18 +108,20 @@ private static bool TryReadContext(XmlUnmarshallerContext context)
             }
         }
 
-        private static ErrorResponseUnmarshaller instance;
+        private static XmlErrorResponseUnmarshaller instance;
 
+#pragma warning disable CA1024 // Use properties where appropriate
         /// <summary>
         /// Return an instance of and ErrorResponseUnmarshaller.
         /// </summary>
         /// <returns></returns>
-        public static ErrorResponseUnmarshaller GetInstance()
+        public static XmlErrorResponseUnmarshaller GetInstance()
         {
             if (instance == null)
-                instance = new ErrorResponseUnmarshaller();
+                instance = new XmlErrorResponseUnmarshaller();
 
             return instance;
         }
     }
+#pragma warning restore CA1024 // Use properties where appropriate
 }
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Transform/XmlUnmarshallerContext.cs b/sdk/src/Core/Amazon.Runtime/Internal/Transform/XmlUnmarshallerContext.cs
new file mode 100644
index 000000000000..39b3b7cbd9df
--- /dev/null
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Transform/XmlUnmarshallerContext.cs
@@ -0,0 +1,420 @@
+using Amazon.Runtime.Internal.Util;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Xml;
+
+namespace Amazon.Runtime.Internal.Transform
+{
+    /// <summary>
+    /// Wrap an <c>XmltextReader</c> for simulating an event stream.
+    /// 
+    /// Each <c>Read()</c> operation goes either to the next element or next attribute within
+    /// the current element. <c>TestExpression()</c> is used to match the current event
+    /// to an xpath expression. The general pattern looks like this:
+    /// <code>
+    /// UnmarshallerContext context = new UnmarshallerContext(...);
+    /// while (context.Read())
+    /// {
+    ///     if (context.TestExpresion("path/to/element"))
+    ///     {
+    ///         myObject.stringMember = stringUnmarshaller.GetInstance().Unmarshall(context);
+    ///         continue;
+    ///     }
+    ///     if (context.TestExpression("path/to/@attribute"))
+    ///         myObject.MyComplexTypeMember = MyComplexTypeUnmarshaller.GetInstance().Unmarshall(context);
+    /// }
+    /// </code>
+    /// </summary>
+    public class XmlUnmarshallerContext : UnmarshallerContext
+    {
+        #region Private members
+
+        private static HashSet<XmlNodeType> nodesToSkip = new HashSet<XmlNodeType>
+        {
+            XmlNodeType.None,
+            XmlNodeType.XmlDeclaration,
+            XmlNodeType.Comment,
+            XmlNodeType.DocumentType,
+            XmlNodeType.CDATA,
+            XmlNodeType.Whitespace
+        };
+
+        private StreamReader streamReader;
+        private XmlTextReader _xmlTextReader;
+        private Stack<string> stack = new Stack<string>();
+        private string stackString = "";
+        private Dictionary<string, string> attributeValues;
+        private List<string> attributeNames;
+        private IEnumerator<string> attributeEnumerator;
+        private XmlNodeType nodeType;
+        private string nodeContent = String.Empty;
+        private bool disposed = false;
+        private bool currentlyProcessingEmptyElement;
+
+        public Stream Stream
+        {
+            get
+            {
+                return streamReader.BaseStream;
+            }
+        }
+
+        /// <remarks>
+        /// Despite Microsoft's recommendation to use XmlReader for .NET Framework 2.0 or greater 
+        /// (https://docs.microsoft.com/en-us/dotnet/api/system.xml.xmltextreader#remarks), this class
+        /// intentionally uses XmlTextReader to handle the XML related object key constraints 
+        /// for S3 (https://docs.aws.amazon.com/AmazonS3/latest/userguide/object-keys.html).
+        /// </remarks>
+        private XmlTextReader XmlReader
+        {
+            get
+            {
+                if (_xmlTextReader == null)
+                {
+                    _xmlTextReader = new XmlTextReader(streamReader);
+                    _xmlTextReader.WhitespaceHandling = WhitespaceHandling.All;
+                    _xmlTextReader.DtdProcessing = DtdProcessing.Ignore;
+                }
+                return _xmlTextReader;
+            }
+        }
+
+        #endregion
+
+        #region Constructors
+
+        /// <summary>
+        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
+        /// </summary>
+        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
+        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
+        /// <param name="responseData">Response data coming back from the request</param>
+        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
+        public XmlUnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException = false)
+            : this(responseStream, maintainResponseBody, responseData, isException, null)
+        {
+        }
+
+        /// <summary>
+        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
+        /// </summary>
+        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
+        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
+        /// <param name="responseData">Response data coming back from the request</param>
+        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
+        /// <param name="requestContext">Context for the request that produced this response</param>
+        public XmlUnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException, IRequestContext requestContext)
+        {
+            if (isException)
+            {
+                this.WrappingStream = new CachingWrapperStream(responseStream);
+            }
+            else if (maintainResponseBody)
+            {
+                this.WrappingStream = new CachingWrapperStream(responseStream, AWSConfigs.LoggingConfig.LogResponsesSizeLimit);
+            }
+
+            if (isException || maintainResponseBody)
+            {
+                responseStream = this.WrappingStream;
+            }
+            // If the unmarshaller context is being called internally without there being a http response then the response data would be null
+            if (responseData != null)
+            {
+                long contentLength;
+                bool parsedContentLengthHeader = long.TryParse(responseData.GetHeaderValue("Content-Length"), out contentLength);
+
+                if (parsedContentLengthHeader && contentLength == 0)
+                {
+                    IsEmptyResponse = true;
+                }
+                // Validate flexible checksums if we know the content length and the behavior was opted in to on the request
+                if (parsedContentLengthHeader && responseData.ContentLength == contentLength &&
+                        string.IsNullOrEmpty(responseData.GetHeaderValue("Content-Encoding")) &&
+                        requestContext?.OriginalRequest?.CoreChecksumMode == CoreChecksumResponseBehavior.ENABLED)
+                {
+                    SetupFlexibleChecksumStream(responseData, responseStream, contentLength, requestContext);
+                }
+            }
+
+            streamReader = new StreamReader(this.FlexibleChecksumStream ?? responseStream);
+
+            this.WebResponseData = responseData;
+            this.MaintainResponseBody = maintainResponseBody;
+            this.IsException = isException;
+        }
+
+        #endregion
+
+        #region Overrides
+
+        /// <summary>
+        /// The current XML path that is being unmarshalled.
+        /// </summary>
+        public override string CurrentPath
+        {
+            get { return this.stackString; }
+        }
+
+        /// <summary>
+        ///     Returns the element depth of the parser's current position in the XML
+        ///     document being parsed.
+        /// </summary>
+        public override int CurrentDepth
+        {
+            get { return stack.Count; }
+        }
+
+        /// <summary>
+        /// True if <c>NodeType</c> is <c>Element</c>.
+        /// </summary>
+        public override bool IsStartElement
+        {
+            get { return this.nodeType == XmlNodeType.Element; }
+        }
+
+        /// <summary>
+        /// True if <c>NodeType</c> is <c>EndElement</c>.
+        /// </summary>
+        public override bool IsEndElement
+        {
+            get { return this.nodeType == XmlNodeType.EndElement; }
+        }
+
+        /// <summary>
+        /// True if the context is at the start of the document.
+        /// </summary>
+        public override bool IsStartOfDocument
+        {
+            get { return XmlReader.ReadState == ReadState.Initial; }
+        }
+
+        #endregion
+
+        #region Public methods
+
+        /// <summary>
+        ///     Returns the text contents of the current element being parsed.
+        /// </summary>
+        /// <returns>
+        ///     The text contents of the current element being parsed.
+        /// </returns>
+        public string ReadText()
+        {
+            if (this.nodeType == XmlNodeType.Attribute)
+            {
+                return (attributeValues[attributeEnumerator.Current]);
+            }
+            else
+            {
+                return nodeContent;
+            }
+        }
+
+        /// <summary>
+        /// Reads the next token at depth greater than or equal to target depth.
+        /// </summary>
+        /// <param name="targetDepth">Tokens are read at depth greater than or equal to target depth.</param>
+        /// <returns>True if a token was read and current depth is greater than or equal to target depth.</returns>
+        public bool ReadAtDepth(int targetDepth)
+        {
+            return Read() && this.CurrentDepth >= targetDepth;
+        }
+
+        /// <summary>
+        /// Reads to the next node in the XML document, and updates the context accordingly.
+        /// </summary>
+        /// <returns>
+        /// True if a node was read, false if there are no more elements to read./
+        /// </returns>
+        public virtual bool Read()
+        {
+            if (attributeEnumerator != null && attributeEnumerator.MoveNext())
+            {
+                this.nodeType = XmlNodeType.Attribute;
+                stackString = string.Format(CultureInfo.InvariantCulture, "{0}/@{1}", StackToPath(stack), attributeEnumerator.Current);
+            }
+            else
+            {
+                // Skip some nodes
+                if (nodesToSkip.Contains(XmlReader.NodeType))
+                    XmlReader.Read();
+
+                if (currentlyProcessingEmptyElement)
+                {
+                    nodeType = XmlNodeType.EndElement;
+                    stack.Pop();
+                    stackString = StackToPath(stack);
+                    XmlReader.Read();
+                    currentlyProcessingEmptyElement = false;
+                }
+                else if (XmlReader.IsEmptyElement)
+                {
+                    //This is a shorthand form of an empty element <element /> and we want to allow it
+                    nodeType = XmlNodeType.Element;
+                    stack.Push(XmlReader.LocalName);
+                    stackString = StackToPath(stack);
+                    currentlyProcessingEmptyElement = true;
+                    nodeContent = String.Empty;
+
+                    //Defer reading so that on next pass we can treat this same element as the end element.
+                }
+                else
+                {
+                    switch (XmlReader.NodeType)
+                    {
+                        case XmlNodeType.EndElement:
+                            this.nodeType = XmlNodeType.EndElement;
+                            stack.Pop();
+                            stackString = StackToPath(stack);
+                            XmlReader.Read();
+                            break;
+                        case XmlNodeType.Element:
+                            nodeType = XmlNodeType.Element;
+                            stack.Push(XmlReader.LocalName);
+                            stackString = StackToPath(stack);
+                            this.ReadElement();
+                            break;
+                    }
+                }
+            }
+
+            bool moreDataAvailable =
+                XmlReader.ReadState != ReadState.EndOfFile &&
+                XmlReader.ReadState != ReadState.Error &&
+                XmlReader.ReadState != ReadState.Closed;
+            return moreDataAvailable;
+        }
+        /// <summary>
+        /// True if <c>NodeType</c> is <c>Attribute</c>.
+        /// </summary>
+        public bool IsAttribute
+        {
+            get { return this.nodeType == XmlNodeType.Attribute; }
+        }
+
+        #endregion
+
+        #region Private Methods
+
+        private static string StackToPath(Stack<string> stack)
+        {
+            string path = null;
+            foreach (string s in stack.ToArray())
+            {
+                path = null == path ? s : string.Format(CultureInfo.InvariantCulture, "{0}/{1}", s, path);
+            }
+            return "/" + path;
+        }
+
+        // Move to the next element, cache the attributes collection
+        // and attempt to cache the inner text of the element if applicable.
+        private void ReadElement()
+        {
+            if (XmlReader.HasAttributes)
+            {
+                attributeValues = new Dictionary<string, string>();
+                attributeNames = new List<string>();
+                while (XmlReader.MoveToNextAttribute())
+                {
+                    attributeValues.Add(XmlReader.LocalName, XmlReader.Value);
+                    attributeNames.Add(XmlReader.LocalName);
+                }
+                attributeEnumerator = attributeNames.GetEnumerator();
+            }
+            XmlReader.MoveToElement();
+            XmlReader.Read();
+
+            if (XmlReader.NodeType == XmlNodeType.Text || XmlReader.NodeType == XmlNodeType.Whitespace)
+                nodeContent = XmlReader.ReadContentAsString();
+            else
+                nodeContent = String.Empty;
+        }
+
+        #endregion
+
+        protected override void Dispose(bool disposing)
+        {
+            if (!this.disposed)
+            {
+                if (disposing)
+                {
+                    if (streamReader != null)
+                    {
+                        streamReader.Dispose();
+                        streamReader = null;
+                    }
+                    if (_xmlTextReader != null)
+                    {
+#if NETSTANDARD
+                        _xmlTextReader.Dispose();
+#else
+                        _xmlTextReader.Close();
+#endif
+                        _xmlTextReader = null;
+                    }
+                }
+                disposed = true;
+            }
+            base.Dispose(disposing);
+        }
+    }
+
+    public class EC2UnmarshallerContext : XmlUnmarshallerContext
+    {
+        /// <summary>
+        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
+        /// </summary>
+        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
+        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
+        /// <param name="responseData">Response data coming back from the request</param>
+        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
+        public EC2UnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException = false)
+            : base(responseStream, maintainResponseBody, responseData, isException)
+        {
+        }
+
+        /// <summary>
+        /// Wrap an XmlTextReader with state for event-based parsing of an XML stream.
+        /// </summary>
+        /// <param name="responseStream"><c>Stream</c> with the XML from a service response.</param>
+        /// <param name="maintainResponseBody"> If set to true, maintains a copy of the complete response body constraint to log response size as the stream is being read.</param>
+        /// <param name="responseData">Response data coming back from the request</param>
+        /// <param name="isException">If set to true, maintains a copy of the complete response body as the stream is being read.</param>
+        /// <param name="requestContext">Context for the request that produced this response</param>
+        public EC2UnmarshallerContext(Stream responseStream, bool maintainResponseBody, IWebResponseData responseData, bool isException, IRequestContext requestContext)
+            : base(responseStream, maintainResponseBody, responseData, isException, requestContext)
+        {
+        }
+
+        /// <summary>
+        /// RequestId value, if found in response
+        /// </summary>
+        public string RequestId { get; private set; }
+
+        /// <summary>
+        /// Reads to the next node in the XML document, and updates the context accordingly.
+        /// If node is RequestId, reads the contents and stores in RequestId property.
+        /// </summary>
+        /// <returns>
+        /// True if a node was read, false if there are no more elements to read./
+        /// </returns>
+        public override bool Read()
+        {
+            bool result = base.Read();
+            if (RequestId == null)
+            {
+                if (IsStartElement && TestExpression("RequestId", 2))
+                {
+                    RequestId = StringUnmarshaller.GetInstance().Unmarshall(this);
+                }
+            }
+            return result;
+        }
+    }
+}
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Util/JsonConstants.cs b/sdk/src/Core/Amazon.Runtime/Internal/Util/JsonConstants.cs
new file mode 100644
index 000000000000..f1470b5e3cc2
--- /dev/null
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Util/JsonConstants.cs
@@ -0,0 +1,29 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ * 
+ *  http://aws.amazon.com/apache2.0
+ * 
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Amazon.Runtime.Internal.Util
+{
+    /// <summary>
+    /// Constants used in JSON unmarshalling.
+    /// </summary>
+    public static class JsonConstants
+    {
+        private static byte[] _utf8BomBytes = new byte[] { 0xEF, 0xBB, 0xBF };
+        public static ReadOnlySpan<byte>  Utf8Bom => _utf8BomBytes;
+    }
+}
diff --git a/sdk/src/Core/Amazon.Runtime/Internal/Util/StreamingUtf8JsonReader.cs b/sdk/src/Core/Amazon.Runtime/Internal/Util/StreamingUtf8JsonReader.cs
new file mode 100644
index 000000000000..27a7d50536b7
--- /dev/null
+++ b/sdk/src/Core/Amazon.Runtime/Internal/Util/StreamingUtf8JsonReader.cs
@@ -0,0 +1,181 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ * 
+ *  http://aws.amazon.com/apache2.0
+ * 
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+using System;
+using System.Buffers;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Text;
+using System.Text.Json;
+using System.Threading.Tasks;
+
+namespace Amazon.Runtime.Internal.Util
+{
+    /// <summary>
+    /// A wrapper around Utf8JsonReader that can handle reading from a stream.
+    /// </summary>
+    public ref struct StreamingUtf8JsonReader
+    {
+        private Utf8JsonReader _reader;
+        private static JsonReaderOptions _jsonOptions = new JsonReaderOptions
+        {
+            AllowTrailingCommas = true
+        };
+        /// <summary>
+        /// The UTF8JsonReader attached to the instance. 
+        /// </summary>
+        public Utf8JsonReader Reader
+        {
+            get
+            {
+                return _reader;
+            }
+        }
+
+        private Stream _stream;
+        private byte[] _buffer;
+
+        /// <summary>
+        /// Initializes a new instance of the StreamingUtf8JsonReader. Upon initialization the reader will read from the stream and fill the buffer.
+        /// If a UTF8 BOM is present in the stream, it will be skipped. Unless <see cref="AWSConfigs.StreamingUtf8JsonReaderBufferSize"/> is set, the default
+        /// buffer size for buffering data from the stream will be 4096. You can also use the constructor that accepts bufferSize to change this value.
+        /// </summary>
+        /// <param name="stream">the stream containing the data</param>
+        public StreamingUtf8JsonReader(Stream stream) : this(stream, AWSConfigs.StreamingUtf8JsonReaderBufferSize ?? 4096)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the StreamingUtf8JsonReader. Upon initialization the reader will read from the stream and fill the buffer.
+        /// If a UTF8 BOM is present in the stream, it will be skipped.
+        /// </summary>
+        /// <param name="stream">the stream containing the data</param>
+        /// <param name="bufferSize">the size of the buffer when reading data from the stream</param>
+        /// <exception cref="ArgumentException"></exception>
+        public StreamingUtf8JsonReader(Stream stream, int bufferSize)
+        {
+            if (stream is null)
+                throw new ArgumentException("Stream must not be null. Please initialize a stream and pass it into the constructor.");
+
+            _stream = stream;
+            _buffer = ArrayPool<byte>.Shared.Rent(bufferSize);
+            int utf8BomLength = JsonConstants.Utf8Bom.Length;
+            Debug.Assert(_buffer.Length >= utf8BomLength);
+
+            int bytesRead = _stream.Read(_buffer, 0, _buffer.Length);
+            int start = 0;
+            if (_buffer.AsSpan().StartsWith(JsonConstants.Utf8Bom))
+            {
+                start += utf8BomLength;
+                bytesRead -= utf8BomLength;
+            }
+
+            _reader = new Utf8JsonReader(_buffer.AsSpan(start, bytesRead), isFinalBlock: bytesRead == 0, new JsonReaderState(_jsonOptions));
+        }
+
+        /// <summary>
+        /// Reads data from the buffer and fetches more data from the stream to fill the buffer it more data exists.
+        /// </summary>
+        /// <returns>true if there is more data, false otherwise.</returns>
+        public bool Read()
+        {
+            // hasMoreData can return false if the value starts in one buffer and leaks into the next buffer
+            bool hasMoreData = _reader.Read();
+
+            while (!hasMoreData)
+            {
+                if (_reader.IsFinalBlock)
+                {
+                    ArrayPool<byte>.Shared.Return(_buffer);
+                    break;
+                }
+
+                GetMoreBytesFromStream(_stream, ref _buffer, ref _reader);
+
+                hasMoreData = _reader.Read();
+            }
+
+            return hasMoreData;
+        }
+
+        private static void GetMoreBytesFromStream(Stream stream, ref byte[] buffer, ref Utf8JsonReader reader)
+        {
+            int bytesRead = 0;
+            ReadOnlySpan<byte> leftover = buffer.AsSpan().Slice((int)reader.BytesConsumed);
+            if (reader.BytesConsumed < buffer.Length)
+            {
+                // If BytesConsumed is 0 that means that the previous Read failed because the JSON token was too large to fit in the buffer.
+                // In that case we need to resize the buffer and try again to read the JSON token.
+                if (reader.BytesConsumed == 0)
+                {
+                    var resizedBuffer = ArrayPool<byte>.Shared.Rent(Math.Min(int.MaxValue, (buffer.Length * 2)));
+                    Logger.GetLogger(typeof(StreamingUtf8JsonReader)).DebugFormat("Resizing buffer from {0} to {1}", buffer.Length, resizedBuffer.Length);
+                    // copy over the data from the previous read's buffer to the newly resized buffer.
+                    buffer.AsSpan().CopyTo(resizedBuffer);
+                    // return the previous buffer to the pool and set the new buffer to equal the resized buffer.
+                    ArrayPool<byte>.Shared.Return(buffer);
+                    buffer = resizedBuffer;
+                    // fill the new resized buffer with data from the stream. the offset MUST be leftover.Length 
+                    // so we don't overwrite the data that was copied from the previous buffer, and the number of bytes
+                    // we read must be buffer.Length - leftover.Length which is just the second half of the buffer.
+                    bytesRead = FillBuffer(stream, ref buffer, leftover.Length, buffer.Length - leftover.Length);
+                    var resizedSpan = buffer.AsSpan(0, bytesRead + leftover.Length);
+                    reader = new Utf8JsonReader(resizedSpan, isFinalBlock: bytesRead == 0, reader.CurrentState);
+                    // early return since we have a reader
+                    return;
+                }
+                else
+                {
+                    // Move the unprocessed data from the buffer to the start and fill
+                    // remaining space in the buffer with new content from the stream.
+                    leftover.CopyTo(buffer);
+                    bytesRead = FillBuffer(stream, ref buffer, leftover.Length, buffer.Length - leftover.Length);
+                }
+            }
+            else
+            {
+                bytesRead = FillBuffer(stream, ref buffer, 0, buffer.Length);
+            }
+
+            if (bytesRead == 0)
+            {
+                // empty buffer will be returned 
+                reader = new Utf8JsonReader(buffer.AsSpan(0, bytesRead), isFinalBlock: true, reader.CurrentState);
+                return;
+            }
+
+            // passing in 0 for the start position and bytesRead + leftover.Length as the span length is safe here because even if we are on the last buffer block,
+            // and leftover is junk, that means bytesRead would've been zero and control would flow through the if block above.
+            reader = new Utf8JsonReader(buffer.AsSpan(0, bytesRead + leftover.Length), isFinalBlock: ((bytesRead + leftover.Length) != buffer.Length || bytesRead == 0), reader.CurrentState);
+        }
+
+        private static int FillBuffer(Stream stream, ref byte[] buffer, int offset, int bytesToRead)
+        {
+            if (stream is null)
+                throw new ArgumentNullException("stream must be populated.");
+            int bytesRead = 0;
+            while (bytesToRead > 0)
+            {
+                int read = stream.Read(buffer, offset, bytesToRead);
+                if (read == 0) break; // End of stream
+                offset += read;
+                bytesToRead -= read;
+                bytesRead += read;
+            }
+
+            return bytesRead;
+        }
+    }
+}
diff --git a/sdk/src/Core/Amazon.Util/AWSSDKUtils.cs b/sdk/src/Core/Amazon.Util/AWSSDKUtils.cs
index 2d38a6a47936..6d27ee6e3578 100644
--- a/sdk/src/Core/Amazon.Util/AWSSDKUtils.cs
+++ b/sdk/src/Core/Amazon.Util/AWSSDKUtils.cs
@@ -848,6 +848,13 @@ public static void CopyStream(Stream source, Stream destination, int bufferSize)
         {
             source.CopyTo(destination, bufferSize);
         }
+
+        public static void CopyStreamAndSetPositionToZero(Stream source, Stream destination)
+        {
+            source.CopyTo(destination);
+            source.Position = 0;
+            destination.Position = 0;
+        }
 #endregion
 
 #region Public Methods and Properties
diff --git a/sdk/src/Core/Amazon.Util/Internal/RootConfig.cs b/sdk/src/Core/Amazon.Util/Internal/RootConfig.cs
index 2550fe805fa6..3c3b17a4ac8d 100644
--- a/sdk/src/Core/Amazon.Util/Internal/RootConfig.cs
+++ b/sdk/src/Core/Amazon.Util/Internal/RootConfig.cs
@@ -47,6 +47,7 @@ public RegionEndpoint RegionEndpoint
         public bool? CSMEnabled { get; set; }
         public string CSMClientId { get; set; }
         public int? CSMPort { get; set; }
+        public int? StreamingUtf8JsonReaderBufferSize { get; set; }
 
 #if NET8_0_OR_GREATER
         public bool DisableDangerousDisablePathAndQueryCanonicalization { get; set; }
diff --git a/sdk/src/Core/GlobalSuppressions.cs b/sdk/src/Core/GlobalSuppressions.cs
index 359bd1bc2926..69264c720658 100644
--- a/sdk/src/Core/GlobalSuppressions.cs
+++ b/sdk/src/Core/GlobalSuppressions.cs
@@ -1,4 +1,4 @@
-/*
+/*
  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License").
@@ -41,11 +41,14 @@
 [module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.IUnmarshaller`2", MessageId = "T")]
 [module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.DictionaryUnmarshaller`4", MessageId = "T")]
 [module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.IMarshaller`2", MessageId = "T")]
-[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.ListUnmarshaller`2", MessageId = "T")]
-[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.KeyValueUnmarshaller`4", MessageId = "T")]
 [module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.IRequestMarshaller`2", MessageId = "T")]
 [module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.AutoConstructedDictionary`2", MessageId = "T")]
-
+[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.XmlKeyValueUnmarshaller`4", MessageId = "T")]
+[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.JsonKeyValueUnmarshaller`4", MessageId = "T")]
+[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.XmlDictionaryUnmarshaller`2", MessageId = "T")]
+[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.JsonDictionaryUnmarshaller`2", MessageId = "T")]
+[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.XmlListUnmarshaller`2", MessageId = "T")]
+[module: SuppressMessage("Microsoft.Naming", "CA1715:IdentifiersShouldHaveCorrectPrefix", Scope = "type", Target = "Amazon.Runtime.Internal.Transform.JsonListUnmarshaller`2", MessageId = "T")]
 // Identifiers should not contain type names
 [module: SuppressMessage("Microsoft.Naming", "CA1720:IdentifiersShouldNotContainTypeNames", Scope = "member", Target = "Amazon.Runtime.Internal.Auth.AWS4PreSignedUrlSigner.#MaxAWS4PreSignedUrlExpiry", MessageId = "signed")]
 [module: SuppressMessage("Microsoft.Naming", "CA1720:IdentifiersShouldNotContainTypeNames", Scope = "member", Target = "Amazon.Runtime.Internal.Auth.AWS4Signer.#FormatDateTime(System.DateTime,System.String)", MessageId = "string")]
@@ -426,6 +429,8 @@
 // Amazon.Runtime.Internal.Signer type conflicts with Amazon.Signer service namespace. 
 [module: SuppressMessage("Microsoft.Naming", "CA1724:TypeNamesShouldNotMatchNamespaces", Scope = "type", Target = "Amazon.Runtime.Internal.Signer")]
 
+// Override Equals and operator equals on value types
+[module: SuppressMessage("Performance","CA1815:Override equals and operator equals on value types",Scope = "type",Target = "T:Amazon.Runtime.Internal.Util.StreamingUtf8JsonReader")]
 
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Naming", "CA1720:Identifier contains type name", Scope = "type", Target = "~T:ThirdParty.Json.LitJson.JsonType")]
 [assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1010:Collections should implement generic interface", Scope = "type", Target = "~T:Amazon.MissingTypes.IOrderedDictionary")]
diff --git a/sdk/src/Core/ThirdParty/RuntimeBackports/ArrayPoolExtensions.cs b/sdk/src/Core/ThirdParty/RuntimeBackports/ArrayPoolExtensions.cs
new file mode 100644
index 000000000000..fd67c7dc785a
--- /dev/null
+++ b/sdk/src/Core/ThirdParty/RuntimeBackports/ArrayPoolExtensions.cs
@@ -0,0 +1,100 @@
+// Taken from https://raw.githubusercontent.com/CommunityToolkit/dotnet/refs/heads/main/src/CommunityToolkit.HighPerformance/Extensions/ArrayPoolExtensions.cs
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Buffers;
+using System.Diagnostics.CodeAnalysis;
+#nullable enable
+namespace ThirdParty.RuntimeBackports
+{
+    /// <summary>
+    /// Helpers for working with the <see cref="ArrayPool{T}"/> type.
+    /// </summary>
+    public static class ArrayPoolExtensions
+    {
+        /// <summary>
+        /// Changes the number of elements of a rented one-dimensional array to the specified new size.
+        /// </summary>
+        /// <typeparam name="T">The type of items into the target array to resize.</typeparam>
+        /// <param name="pool">The target <see cref="ArrayPool{T}"/> instance to use to resize the array.</param>
+        /// <param name="array">The rented <typeparamref name="T"/> array to resize, or <see langword="null"/> to create a new array.</param>
+        /// <param name="newSize">The size of the new array.</param>
+        /// <param name="clearArray">Indicates whether the contents of the array should be cleared before reuse.</param>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="newSize"/> is less than 0.</exception>
+        /// <remarks>When this method returns, the caller must not use any references to the old array anymore.</remarks>
+        public static void Resize<T>(this ArrayPool<T> pool, ref T[]? array, int newSize, bool clearArray = false)
+        {
+            // If the old array is null, just create a new one with the requested size
+            if (array is null)
+            {
+                array = pool.Rent(newSize);
+
+                return;
+            }
+
+            // If the new size is the same as the current size, do nothing
+            if (array.Length == newSize)
+            {
+                return;
+            }
+
+            // Rent a new array with the specified size, and copy as many items from the current array
+            // as possible to the new array. This mirrors the behavior of the Array.Resize API from
+            // the BCL: if the new size is greater than the length of the current array, copy all the
+            // items from the original array into the new one. Otherwise, copy as many items as possible,
+            // until the new array is completely filled, and ignore the remaining items in the first array.
+            T[] newArray = pool.Rent(newSize);
+            int itemsToCopy = Math.Min(array.Length, newSize);
+
+            Array.Copy(array, 0, newArray, 0, itemsToCopy);
+
+            pool.Return(array, clearArray);
+
+            array = newArray;
+        }
+
+        /// <summary>
+        /// Ensures that when the method returns <paramref name="array"/> is not null and is at least <paramref name="capacity"/> in length.
+        /// Contents of <paramref name="array"/> are not copied if a new array is rented.
+        /// </summary>
+        /// <typeparam name="T">The type of items into the target array given as input.</typeparam>
+        /// <param name="pool">The target <see cref="ArrayPool{T}"/> instance used to rent and/or return the array.</param>
+        /// <param name="array">The rented <typeparamref name="T"/> array to ensure capacity for, or <see langword="null"/> to rent a new array.</param>
+        /// <param name="capacity">The minimum length of <paramref name="array"/> when the method returns.</param>
+        /// <param name="clearArray">Indicates whether the contents of the array should be cleared if returned to the pool.</param>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="capacity"/> is less than 0.</exception>
+        /// <remarks>When this method returns, the caller must not use any references to the old array anymore.</remarks>
+        public static void EnsureCapacity<T>(this ArrayPool<T> pool, ref T[]? array, int capacity, bool clearArray = false)
+        {
+            if (capacity < 0)
+            {
+                ThrowArgumentOutOfRangeExceptionForNegativeArrayCapacity();
+            }
+
+            if (array is null)
+            {
+                array = pool.Rent(capacity);
+            }
+            else if (array.Length < capacity)
+            {
+                // Ensure rent succeeds before returning the original array to the pool
+                T[] newArray = pool.Rent(capacity);
+
+                pool.Return(array, clearArray);
+
+                array = newArray;
+            }
+        }
+
+        /// <summary>
+        /// Throws an <see cref="ArgumentOutOfRangeException"/> when the "capacity" parameter is negative.
+        /// </summary>
+        private static void ThrowArgumentOutOfRangeExceptionForNegativeArrayCapacity()
+        {
+            throw new ArgumentOutOfRangeException("capacity", "The array capacity must be a positive number.");
+        }
+    }
+}
+
diff --git a/sdk/src/Core/ThirdParty/RuntimeBackports/BitOperations.cs b/sdk/src/Core/ThirdParty/RuntimeBackports/BitOperations.cs
new file mode 100644
index 000000000000..58612b9c820b
--- /dev/null
+++ b/sdk/src/Core/ThirdParty/RuntimeBackports/BitOperations.cs
@@ -0,0 +1,37 @@
+// Taken from https://raw.githubusercontent.com/CommunityToolkit/dotnet/refs/heads/main/src/CommunityToolkit.HighPerformance/Helpers/Internals/BitOperations.cs
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Text;
+
+namespace ThirdParty.RuntimeBackports
+{
+    internal static class BitOperations
+    {
+        /// <summary>
+        /// Round the given integral value up to a power of 2.
+        /// </summary>
+        /// <param name="value">The value.</param>
+        /// <returns>
+        /// The smallest power of 2 which is greater than or equal to <paramref name="value"/>.
+        /// If <paramref name="value"/> is 0 or the result overflows, returns 0.
+        /// </returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static unsafe uint RoundUpToPowerOf2(uint value)
+        {
+            // Based on https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
+            --value;
+            value |= value >> 1;
+            value |= value >> 2;
+            value |= value >> 4;
+            value |= value >> 8;
+            value |= value >> 16;
+
+            return value + 1;
+        }
+    }
+}
diff --git a/sdk/src/Core/ThirdParty/RuntimeBackports/_netstandard/ArrayPoolBufferWriter.cs b/sdk/src/Core/ThirdParty/RuntimeBackports/_netstandard/ArrayPoolBufferWriter.cs
new file mode 100644
index 000000000000..84de68665d8e
--- /dev/null
+++ b/sdk/src/Core/ThirdParty/RuntimeBackports/_netstandard/ArrayPoolBufferWriter.cs
@@ -0,0 +1,385 @@
+// partially adapted from https://raw.githubusercontent.com/CommunityToolkit/dotnet/refs/heads/main/src/CommunityToolkit.HighPerformance/Buffers/ArrayPoolBufferWriter%7BT%7D.cs
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Buffers;
+using System.Diagnostics;
+using System.Numerics;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using ThirdParty.RuntimeBackports;
+#if NET8_0_OR_GREATER
+using BitOperations = System.Numerics.BitOperations;
+#else
+using BitOperations = ThirdParty.RuntimeBackports.BitOperations;
+#endif
+#nullable enable
+namespace ThirdParty.RuntimeBackports
+{
+    /// <summary>
+    /// Represents a heap-based, array-backed output sink into which <typeparamref name="T"/> data can be written.
+    /// </summary>
+    /// <typeparam name="T">The type of items to write to the current instance.</typeparam>
+    /// <remarks>
+    /// This is a custom <see cref="IBufferWriter{T}"/> implementation that replicates the
+    /// functionality and API surface of the array-based buffer writer available in
+    /// .NET Standard 2.1, with the main difference being the fact that in this case
+    /// the arrays in use are rented from the shared <see cref="ArrayPool{T}"/> instance,
+    /// and that <see cref="ArrayPoolBufferWriter{T}"/> is also available on .NET Standard 2.0.
+    /// </remarks>
+    public sealed class ArrayPoolBufferWriter<T> : IBufferWriter<T>, IMemoryOwner<T>
+    {
+        /// <summary>
+        /// The default buffer size to use to expand empty arrays.
+        /// </summary>
+        private const int DefaultInitialBufferSize = 256;
+
+        /// <summary>
+        /// The <see cref="ArrayPool{T}"/> instance used to rent <see cref="array"/>.
+        /// </summary>
+        private readonly ArrayPool<T> pool;
+
+        /// <summary>
+        /// The underlying <typeparamref name="T"/> array.
+        /// </summary>
+        private T[]? array;
+
+#pragma warning disable IDE0032 // Use field over auto-property (clearer and faster)
+        /// <summary>
+        /// The starting offset within <see cref="array"/>.
+        /// </summary>
+        private int index;
+#pragma warning restore IDE0032
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ArrayPoolBufferWriter{T}"/> class.
+        /// </summary>
+        public ArrayPoolBufferWriter()
+            : this(ArrayPool<T>.Shared, DefaultInitialBufferSize)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ArrayPoolBufferWriter{T}"/> class.
+        /// </summary>
+        /// <param name="pool">The <see cref="ArrayPool{T}"/> instance to use.</param>
+        public ArrayPoolBufferWriter(ArrayPool<T> pool)
+            : this(pool, DefaultInitialBufferSize)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ArrayPoolBufferWriter{T}"/> class.
+        /// </summary>
+        /// <param name="initialCapacity">The minimum capacity with which to initialize the underlying buffer.</param>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="initialCapacity"/> is not valid.</exception>
+        public ArrayPoolBufferWriter(int initialCapacity)
+            : this(ArrayPool<T>.Shared, initialCapacity)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ArrayPoolBufferWriter{T}"/> class.
+        /// </summary>
+        /// <param name="pool">The <see cref="ArrayPool{T}"/> instance to use.</param>
+        /// <param name="initialCapacity">The minimum capacity with which to initialize the underlying buffer.</param>
+        /// <exception cref="ArgumentOutOfRangeException">Thrown when <paramref name="initialCapacity"/> is not valid.</exception>
+        public ArrayPoolBufferWriter(ArrayPool<T> pool, int initialCapacity)
+        {
+            // Since we're using pooled arrays, we can rent the buffer with the
+            // default size immediately, we don't need to use lazy initialization
+            // to save unnecessary memory allocations in this case.
+            // Additionally, we don't need to manually throw the exception if
+            // the requested size is not valid, as that'll be thrown automatically
+            // by the array pool in use when we try to rent an array with that size.
+            this.pool = pool;
+            array = pool.Rent(initialCapacity);
+            index = 0;
+        }
+
+        /// <inheritdoc/>
+        Memory<T> IMemoryOwner<T>.Memory
+        {
+            // This property is explicitly implemented so that it's hidden
+            // under normal usage, as the name could be confusing when
+            // displayed besides WrittenMemory and GetMemory().
+            // The IMemoryOwner<T> interface is implemented primarily
+            // so that the AsStream() extension can be used on this type,
+            // allowing users to first create a ArrayPoolBufferWriter<byte>
+            // instance to write data to, then get a stream through the
+            // extension and let it take care of returning the underlying
+            // buffer to the shared pool when it's no longer necessary.
+            // Inlining is not needed here since this will always be a callvirt.
+            get => MemoryMarshal.AsMemory(WrittenMemory);
+        }
+
+        /// <inheritdoc/>
+        public ReadOnlyMemory<T> WrittenMemory
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get
+            {
+                T[]? array = this.array;
+
+                if (array is null)
+                {
+                    ThrowObjectDisposedException();
+                }
+
+                return array!.AsMemory(0, index);
+            }
+        }
+
+        /// <inheritdoc/>
+        public ReadOnlySpan<T> WrittenSpan
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get
+            {
+                T[]? array = this.array;
+
+                if (array is null)
+                {
+                    ThrowObjectDisposedException();
+                }
+
+                return array!.AsSpan(0, index);
+            }
+        }
+
+        /// <inheritdoc/>
+        public int WrittenCount
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get => index;
+        }
+
+        /// <inheritdoc/>
+        public int Capacity
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get
+            {
+                T[]? array = this.array;
+
+                if (array is null)
+                {
+                    ThrowObjectDisposedException();
+                }
+
+                return array!.Length;
+            }
+        }
+
+        /// <inheritdoc/>
+        public int FreeCapacity
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get
+            {
+                T[]? array = this.array;
+
+                if (array is null)
+                {
+                    ThrowObjectDisposedException();
+                }
+
+                return array!.Length - index;
+            }
+        }
+
+        /// <inheritdoc/>
+        public void Clear()
+        {
+            T[]? array = this.array;
+
+            if (array is null)
+            {
+                ThrowObjectDisposedException();
+            }
+
+            array.AsSpan(0, index).Clear();
+
+            index = 0;
+        }
+
+        /// <inheritdoc/>
+        public void Advance(int count)
+        {
+            T[]? array = this.array;
+
+            if (array is null)
+            {
+                ThrowObjectDisposedException();
+            }
+
+            if (count < 0)
+            {
+                ThrowArgumentOutOfRangeExceptionForNegativeCount();
+            }
+
+            if (index > array!.Length - count)
+            {
+                ThrowArgumentExceptionForAdvancedTooFar();
+            }
+
+            index += count;
+        }
+
+        /// <inheritdoc/>
+        public Memory<T> GetMemory(int sizeHint = 0)
+        {
+            CheckBufferAndEnsureCapacity(sizeHint);
+
+            return array.AsMemory(index);
+        }
+
+        /// <inheritdoc/>
+        public Span<T> GetSpan(int sizeHint = 0)
+        {
+            CheckBufferAndEnsureCapacity(sizeHint);
+
+            return array.AsSpan(index);
+        }
+
+        /// <summary>
+        /// Gets an <see cref="ArraySegment{T}"/> instance wrapping the underlying <typeparamref name="T"/> array in use.
+        /// </summary>
+        /// <returns>An <see cref="ArraySegment{T}"/> instance wrapping the underlying <typeparamref name="T"/> array in use.</returns>
+        /// <exception cref="ObjectDisposedException">Thrown when the buffer in use has already been disposed.</exception>
+        /// <remarks>
+        /// This method is meant to be used when working with APIs that only accept an array as input, and should be used with caution.
+        /// In particular, the returned array is rented from an array pool, and it is responsibility of the caller to ensure that it's
+        /// not used after the current <see cref="ArrayPoolBufferWriter{T}"/> instance is disposed. Doing so is considered undefined
+        /// behavior, as the same array might be in use within another <see cref="ArrayPoolBufferWriter{T}"/> instance.
+        /// </remarks>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public ArraySegment<T> DangerousGetArray()
+        {
+            T[]? array = this.array;
+
+            if (array is null)
+            {
+                ThrowObjectDisposedException();
+            }
+
+            return new(array!, 0, index);
+        }
+
+        /// <inheritdoc/>
+        public void Dispose()
+        {
+            T[]? array = this.array;
+
+            if (array is null)
+            {
+                return;
+            }
+
+            this.array = null;
+
+            pool.Return(array);
+        }
+
+        /// <inheritdoc/>
+        public override string ToString()
+        {
+            // See comments in MemoryOwner<T> about this
+            if (typeof(T) == typeof(char) &&
+                array is char[] chars)
+            {
+                return new(chars, 0, index);
+            }
+
+            // Same representation used in Span<T>
+            return $"CommunityToolkit.HighPerformance.Buffers.ArrayPoolBufferWriter<{typeof(T)}>[{index}]";
+        }
+
+        /// <summary>
+        /// Ensures that <see cref="array"/> has enough free space to contain a given number of new items.
+        /// </summary>
+        /// <param name="sizeHint">The minimum number of items to ensure space for in <see cref="array"/>.</param>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private void CheckBufferAndEnsureCapacity(int sizeHint)
+        {
+            T[]? array = this.array;
+
+            if (array is null)
+            {
+                ThrowObjectDisposedException();
+            }
+
+            if (sizeHint < 0)
+            {
+                ThrowArgumentOutOfRangeExceptionForNegativeSizeHint();
+            }
+
+            if (sizeHint == 0)
+            {
+                sizeHint = 1;
+            }
+
+            if (sizeHint > array!.Length - index)
+            {
+                ResizeBuffer(sizeHint);
+            }
+        }
+
+        /// <summary>
+        /// Resizes <see cref="array"/> to ensure it can fit the specified number of new items.
+        /// </summary>
+        /// <param name="sizeHint">The minimum number of items to ensure space for in <see cref="array"/>.</param>
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private void ResizeBuffer(int sizeHint)
+        {
+            uint minimumSize = (uint)index + (uint)sizeHint;
+
+            // The ArrayPool<T> class has a maximum threshold of 1024 * 1024 for the maximum length of
+            // pooled arrays, and once this is exceeded it will just allocate a new array every time
+            // of exactly the requested size. In that case, we manually round up the requested size to
+            // the nearest power of two, to ensure that repeated consecutive writes when the array in
+            // use is bigger than that threshold don't end up causing a resize every single time.
+            if (minimumSize > 1024 * 1024)
+            {
+                minimumSize = BitOperations.RoundUpToPowerOf2(minimumSize);
+            }
+
+            pool.Resize(ref array, (int)minimumSize);
+        }
+
+        /// <summary>
+        /// Throws an <see cref="ArgumentOutOfRangeException"/> when the requested count is negative.
+        /// </summary>
+        private static void ThrowArgumentOutOfRangeExceptionForNegativeCount()
+        {
+            throw new ArgumentOutOfRangeException("count", "The count can't be a negative value.");
+        }
+
+        /// <summary>
+        /// Throws an <see cref="ArgumentOutOfRangeException"/> when the size hint is negative.
+        /// </summary>
+        private static void ThrowArgumentOutOfRangeExceptionForNegativeSizeHint()
+        {
+            throw new ArgumentOutOfRangeException("sizeHint", "The size hint can't be a negative value.");
+        }
+
+        /// <summary>
+        /// Throws an <see cref="ArgumentOutOfRangeException"/> when the requested count is negative.
+        /// </summary>
+        private static void ThrowArgumentExceptionForAdvancedTooFar()
+        {
+            throw new ArgumentException("The buffer writer has advanced too far.");
+        }
+
+        /// <summary>
+        /// Throws an <see cref="ObjectDisposedException"/> when <see cref="array"/> is <see langword="null"/>.
+        /// </summary>
+        private static void ThrowObjectDisposedException()
+        {
+            throw new ObjectDisposedException("The current buffer has already been disposed.");
+        }
+    }
+}
+
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AbortIncompleteMultipartUploadUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AbortIncompleteMultipartUploadUnmarshaller.cs
index 9b7352961336..5b768002d1c0 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AbortIncompleteMultipartUploadUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AbortIncompleteMultipartUploadUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   AbortIncompleteMultipartUpload Unmarshaller
      /// </summary>
-    public class AbortIncompleteMultipartUploadUnmarshaller : IUnmarshaller<LifecycleRuleAbortIncompleteMultipartUpload, XmlUnmarshallerContext>, IUnmarshaller<LifecycleRuleAbortIncompleteMultipartUpload, JsonUnmarshallerContext> 
+    public class AbortIncompleteMultipartUploadUnmarshaller : IXmlUnmarshaller<LifecycleRuleAbortIncompleteMultipartUpload, XmlUnmarshallerContext>, IXmlUnmarshaller<LifecycleRuleAbortIncompleteMultipartUpload, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Invoke the unmarshaller
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AccessControlTranslationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AccessControlTranslationUnmarshaller.cs
index 8697c1fa55a3..e66eb344017a 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AccessControlTranslationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AccessControlTranslationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// AccessControlTranslation unmarshaller
     /// </summary>
-    public class AccessControlTranslationUnmarshaller : IUnmarshaller<AccessControlTranslation, XmlUnmarshallerContext>, IUnmarshaller<AccessControlTranslation, JsonUnmarshallerContext>
+    public class AccessControlTranslationUnmarshaller : IXmlUnmarshaller<AccessControlTranslation, XmlUnmarshallerContext>, IXmlUnmarshaller<AccessControlTranslation, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsConfigurationUnmarshaller.cs
index 8c26485fc464..4fead8a6faed 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// AnalyticsConfiguration Unmarshaller
     /// </summary>
-    public class AnalyticsConfigurationUnmarshaller : IUnmarshaller<AnalyticsConfiguration, XmlUnmarshallerContext>, IUnmarshaller<AnalyticsConfiguration, JsonUnmarshallerContext>
+    public class AnalyticsConfigurationUnmarshaller : IXmlUnmarshaller<AnalyticsConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<AnalyticsConfiguration, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsExportDestinationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsExportDestinationUnmarshaller.cs
index 51e903391aa8..c7268f09829e 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsExportDestinationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsExportDestinationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// AnalyticsExportDestinationUnmarshaller
     /// </summary>
-    public class AnalyticsExportDestinationUnmarshaller : IUnmarshaller<AnalyticsExportDestination, XmlUnmarshallerContext>, IUnmarshaller<AnalyticsExportDestination, JsonUnmarshallerContext>
+    public class AnalyticsExportDestinationUnmarshaller : IXmlUnmarshaller<AnalyticsExportDestination, XmlUnmarshallerContext>, IXmlUnmarshaller<AnalyticsExportDestination, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsPredicateListUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsPredicateListUnmarshaller.cs
index 04b186baa766..efcbb10b39f2 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsPredicateListUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsPredicateListUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   AnalyticsFilter Unmarshaller
     /// </summary>
-    public class AnalyticsPredicateListUnmarshaller : IUnmarshaller<List<AnalyticsFilterPredicate>, XmlUnmarshallerContext>, IUnmarshaller<List<AnalyticsFilterPredicate>, JsonUnmarshallerContext>
+    public class AnalyticsPredicateListUnmarshaller : IXmlUnmarshaller<List<AnalyticsFilterPredicate>, XmlUnmarshallerContext>, IXmlUnmarshaller<List<AnalyticsFilterPredicate>, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsS3BucketDestinationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsS3BucketDestinationUnmarshaller.cs
index 0c2f2a7b5261..ca67fa963ef7 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsS3BucketDestinationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/AnalyticsS3BucketDestinationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   AnalyticsS3BucketDestination Unmarshaller
     /// </summary>
-    public class AnalyticsS3BucketDestinationUnmarshaller : IUnmarshaller<AnalyticsS3BucketDestination, XmlUnmarshallerContext>, IUnmarshaller<AnalyticsS3BucketDestination, JsonUnmarshallerContext>
+    public class AnalyticsS3BucketDestinationUnmarshaller : IXmlUnmarshaller<AnalyticsS3BucketDestination, XmlUnmarshallerContext>, IXmlUnmarshaller<AnalyticsS3BucketDestination, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyExistsExceptionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyExistsExceptionUnmarshaller.cs
index 753e0814722f..387ad01e2f06 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyExistsExceptionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyExistsExceptionUnmarshaller.cs
@@ -36,7 +36,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for BucketAlreadyExistsException operation
     /// </summary>  
-    public class BucketAlreadyExistsExceptionUnmarshaller : IErrorResponseUnmarshaller<BucketAlreadyExistsException, XmlUnmarshallerContext>
+    public class BucketAlreadyExistsExceptionUnmarshaller : IXmlErrorResponseUnmarshaller<BucketAlreadyExistsException, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyOwnedByYouExceptionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyOwnedByYouExceptionUnmarshaller.cs
index a6fb41556fa9..84b943fe1686 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyOwnedByYouExceptionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketAlreadyOwnedByYouExceptionUnmarshaller.cs
@@ -36,7 +36,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for BucketAlreadyOwnedByYouException operation
     /// </summary>  
-    public class BucketAlreadyOwnedByYouExceptionUnmarshaller : IErrorResponseUnmarshaller<BucketAlreadyOwnedByYouException, XmlUnmarshallerContext>
+    public class BucketAlreadyOwnedByYouExceptionUnmarshaller : IXmlErrorResponseUnmarshaller<BucketAlreadyOwnedByYouException, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketUnmarshaller.cs
index 0bbfccdcc58c..767c28a40f8f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/BucketUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Bucket Unmarshaller
      /// </summary>
-    public class BucketUnmarshaller : IUnmarshaller<S3Bucket, XmlUnmarshallerContext>, IUnmarshaller<S3Bucket, JsonUnmarshallerContext> 
+    public class BucketUnmarshaller : IXmlUnmarshaller<S3Bucket, XmlUnmarshallerContext>, IXmlUnmarshaller<S3Bucket, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CORSRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CORSRuleUnmarshaller.cs
index 77f5ff5964ed..9b31e7a29138 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CORSRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CORSRuleUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   CORSRule Unmarshaller
      /// </summary>
-    public class CORSRuleUnmarshaller : IUnmarshaller<CORSRule, XmlUnmarshallerContext>, IUnmarshaller<CORSRule, JsonUnmarshallerContext> 
+    public class CORSRuleUnmarshaller : IXmlUnmarshaller<CORSRule, XmlUnmarshallerContext>, IXmlUnmarshaller<CORSRule, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ChecksumUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ChecksumUnmarshaller.cs
index 4d8f8db49e36..bb16b2a7d563 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ChecksumUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ChecksumUnmarshaller.cs
@@ -32,7 +32,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for Checksum Object
     /// </summary>  
-    public class ChecksumUnmarshaller : IUnmarshaller<Checksum, XmlUnmarshallerContext>
+    public class ChecksumUnmarshaller : IXmlUnmarshaller<Checksum, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CloudFunctionConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CloudFunctionConfigurationUnmarshaller.cs
index e540c91f0b4c..e1d2409aa7c3 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CloudFunctionConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CloudFunctionConfigurationUnmarshaller.cs
@@ -24,7 +24,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// LambdaFunction unmarshaller
     /// </summary>
-    public class LambdaFunctionConfigurationUnmarshaller : IUnmarshaller<LambdaFunctionConfiguration, XmlUnmarshallerContext>, IUnmarshaller<LambdaFunctionConfiguration, JsonUnmarshallerContext> 
+    public class LambdaFunctionConfigurationUnmarshaller : IXmlUnmarshaller<LambdaFunctionConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<LambdaFunctionConfiguration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CommonPrefixesItemUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CommonPrefixesItemUnmarshaller.cs
index 67c587527537..93dc3f91803c 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CommonPrefixesItemUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CommonPrefixesItemUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   CommonPrefixesItem Unmarshaller
      /// </summary>
-    public class CommonPrefixesItemUnmarshaller : IUnmarshaller<string, XmlUnmarshallerContext>, IUnmarshaller<string, JsonUnmarshallerContext> 
+    public class CommonPrefixesItemUnmarshaller : IXmlUnmarshaller<string, XmlUnmarshallerContext>, IXmlUnmarshaller<string, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ContentsItemUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ContentsItemUnmarshaller.cs
index d697e26832d8..1cf3a72357e1 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ContentsItemUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ContentsItemUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   ContentsItem Unmarshaller
      /// </summary>
-    public class ContentsItemUnmarshaller : IUnmarshaller<S3Object, XmlUnmarshallerContext>, IUnmarshaller<S3Object, JsonUnmarshallerContext> 
+    public class ContentsItemUnmarshaller : IXmlUnmarshaller<S3Object, XmlUnmarshallerContext>, IXmlUnmarshaller<S3Object, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CreateSessionResponseUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CreateSessionResponseUnmarshaller.cs
index 9347e453a240..4d98185f11fc 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CreateSessionResponseUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/CreateSessionResponseUnmarshaller.cs
@@ -97,7 +97,7 @@ private static void UnmarshallResult(XmlUnmarshallerContext context, CreateSessi
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = S3ErrorResponseUnmarshaller.Instance.Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DefaultRetentionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DefaultRetentionUnmarshaller.cs
index 68381c009160..dd3579ed5a53 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DefaultRetentionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DefaultRetentionUnmarshaller.cs
@@ -35,7 +35,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for DefaultRetention Object
     /// </summary>  
-    public class DefaultRetentionUnmarshaller : IUnmarshaller<DefaultRetention, XmlUnmarshallerContext>, IUnmarshaller<DefaultRetention, JsonUnmarshallerContext>
+    public class DefaultRetentionUnmarshaller : IXmlUnmarshaller<DefaultRetention, XmlUnmarshallerContext>, IXmlUnmarshaller<DefaultRetention, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeleteMarkerReplicationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeleteMarkerReplicationUnmarshaller.cs
index f3995304868b..ed21f330469f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeleteMarkerReplicationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeleteMarkerReplicationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// DeleteMarkerReplication unmarshaller
     /// </summary>
-    public class DeleteMarkerReplicationUnmarshaller : IUnmarshaller<DeleteMarkerReplication, XmlUnmarshallerContext>
+    public class DeleteMarkerReplicationUnmarshaller : IXmlUnmarshaller<DeleteMarkerReplication, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeletedItemUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeletedItemUnmarshaller.cs
index cf8227b8d8bc..2853af7af83a 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeletedItemUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/DeletedItemUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
     ///   DeletedObject Unmarshaller
      /// </summary>
-    public class DeletedObjectUnmarshaller : IUnmarshaller<DeletedObject, XmlUnmarshallerContext>, IUnmarshaller<DeletedObject, JsonUnmarshallerContext> 
+    public class DeletedObjectUnmarshaller : IXmlUnmarshaller<DeletedObject, XmlUnmarshallerContext>, IXmlUnmarshaller<DeletedObject, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EncryptionConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EncryptionConfigurationUnmarshaller.cs
index ca24c1310b88..53da9dee1f15 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EncryptionConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EncryptionConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// EncryptionConfiguration unmarshaller
     /// </summary>
-    public class EncryptionConfigurationUnmarshaller : IUnmarshaller<EncryptionConfiguration, XmlUnmarshallerContext>, IUnmarshaller<EncryptionConfiguration, JsonUnmarshallerContext>
+    public class EncryptionConfigurationUnmarshaller : IXmlUnmarshaller<EncryptionConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<EncryptionConfiguration, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ErrorsItemUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ErrorsItemUnmarshaller.cs
index b486b9aedfed..ad4b3d81b4ba 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ErrorsItemUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ErrorsItemUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   ErrorsItem Unmarshaller
      /// </summary>
-    public class ErrorsItemUnmarshaller : IUnmarshaller<DeleteError, XmlUnmarshallerContext>, IUnmarshaller<DeleteError, JsonUnmarshallerContext> 
+    public class ErrorsItemUnmarshaller : IXmlUnmarshaller<DeleteError, XmlUnmarshallerContext>, IXmlUnmarshaller<DeleteError, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EventBridgeConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EventBridgeConfigurationUnmarshaller.cs
index c97765062aba..a88e83a7c3f1 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EventBridgeConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/EventBridgeConfigurationUnmarshaller.cs
@@ -32,7 +32,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for EventBridgeConfiguration Object
     /// </summary>  
-    public class EventBridgeConfigurationUnmarshaller : IUnmarshaller<EventBridgeConfiguration, XmlUnmarshallerContext>
+    public class EventBridgeConfigurationUnmarshaller : IXmlUnmarshaller<EventBridgeConfiguration, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExistingObjectReplicationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExistingObjectReplicationUnmarshaller.cs
index a189ef85f9c1..2ba62e1df6ba 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExistingObjectReplicationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExistingObjectReplicationUnmarshaller.cs
@@ -21,7 +21,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ExistingObjectReplication unmarshaller
     /// </summary>
-    public class ExistingObjectReplicationUnmarshaller : IUnmarshaller<ExistingObjectReplication, XmlUnmarshallerContext>, IUnmarshaller<ExistingObjectReplication, JsonUnmarshallerContext>
+    public class ExistingObjectReplicationUnmarshaller : IXmlUnmarshaller<ExistingObjectReplication, XmlUnmarshallerContext>, IXmlUnmarshaller<ExistingObjectReplication, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExpirationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExpirationUnmarshaller.cs
index f2ec50d80454..6c736d5979a7 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExpirationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ExpirationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Expiration Unmarshaller
      /// </summary>
-    public class ExpirationUnmarshaller : IUnmarshaller<LifecycleRuleExpiration, XmlUnmarshallerContext>, IUnmarshaller<LifecycleRuleExpiration, JsonUnmarshallerContext> 
+    public class ExpirationUnmarshaller : IXmlUnmarshaller<LifecycleRuleExpiration, XmlUnmarshallerContext>, IXmlUnmarshaller<LifecycleRuleExpiration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterRuleUnmarshaller.cs
index 722806206871..ae0cccf6075b 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterRuleUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
     ///   FilterRule Unmarshaller
      /// </summary>
-    public class FilterRuleUnmarshaller : IUnmarshaller<FilterRule, XmlUnmarshallerContext>, IUnmarshaller<FilterRule, JsonUnmarshallerContext> 
+    public class FilterRuleUnmarshaller : IXmlUnmarshaller<FilterRule, XmlUnmarshallerContext>, IXmlUnmarshaller<FilterRule, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterUnmarshaller.cs
index cf014e770260..10145a11a35f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/FilterUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Filter Unmarshaller
      /// </summary>
-    public class FilterUnmarshaller : IUnmarshaller<Filter, XmlUnmarshallerContext>, IUnmarshaller<Filter, JsonUnmarshallerContext> 
+    public class FilterUnmarshaller : IXmlUnmarshaller<Filter, XmlUnmarshallerContext>, IXmlUnmarshaller<Filter, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GetObjectAttributesPartsUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GetObjectAttributesPartsUnmarshaller.cs
index adf6ec993b24..37d8bd9cb6e5 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GetObjectAttributesPartsUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GetObjectAttributesPartsUnmarshaller.cs
@@ -32,7 +32,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for GetObjectAttributesParts Object
     /// </summary>  
-    public class GetObjectAttributesPartsUnmarshaller : IUnmarshaller<GetObjectAttributesParts, XmlUnmarshallerContext>
+    public class GetObjectAttributesPartsUnmarshaller : IXmlUnmarshaller<GetObjectAttributesParts, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GrantUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GrantUnmarshaller.cs
index a10d6dc9da02..1e9fa044e60f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GrantUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GrantUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Grant Unmarshaller
      /// </summary>
-    public class GrantUnmarshaller : IUnmarshaller<S3Grant, XmlUnmarshallerContext>, IUnmarshaller<S3Grant, JsonUnmarshallerContext> 
+    public class GrantUnmarshaller : IXmlUnmarshaller<S3Grant, XmlUnmarshallerContext>, IXmlUnmarshaller<S3Grant, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GranteeUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GranteeUnmarshaller.cs
index d7e81589f2ec..b87ec7c48a04 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GranteeUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/GranteeUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Grantee Unmarshaller
      /// </summary>
-    public class GranteeUnmarshaller : IUnmarshaller<S3Grantee, XmlUnmarshallerContext>, IUnmarshaller<S3Grantee, JsonUnmarshallerContext> 
+    public class GranteeUnmarshaller : IXmlUnmarshaller<S3Grantee, XmlUnmarshallerContext>, IXmlUnmarshaller<S3Grantee, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/HeadBucketResponseUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/HeadBucketResponseUnmarshaller.cs
index 967dce584e0b..188fa742c150 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/HeadBucketResponseUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/HeadBucketResponseUnmarshaller.cs
@@ -70,7 +70,7 @@ private static void UnmarshallResult(XmlUnmarshallerContext context, HeadBucketR
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = S3ErrorResponseUnmarshaller.Instance.Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InitiatorUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InitiatorUnmarshaller.cs
index 14671416fc05..072b79b360a3 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InitiatorUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InitiatorUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Initiator Unmarshaller
      /// </summary>
-    public class InitiatorUnmarshaller : IUnmarshaller<Initiator, XmlUnmarshallerContext>, IUnmarshaller<Initiator, JsonUnmarshallerContext> 
+    public class InitiatorUnmarshaller : IXmlUnmarshaller<Initiator, XmlUnmarshallerContext>, IXmlUnmarshaller<Initiator, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringConfigurationUnmarshaller.cs
index 9c98a70c911f..8c62a5a4cefe 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Unmarshaller for IntelligentTieringConfiguration
     /// </summary>   
-    public class IntelligentTieringConfigurationUnmarshaller : IUnmarshaller<IntelligentTieringConfiguration, XmlUnmarshallerContext>, IUnmarshaller<IntelligentTieringConfiguration, JsonUnmarshallerContext>
+    public class IntelligentTieringConfigurationUnmarshaller : IXmlUnmarshaller<IntelligentTieringConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<IntelligentTieringConfiguration, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringPredicateListUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringPredicateListUnmarshaller.cs
index 536bfccc55b7..ac9320aee209 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringPredicateListUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/IntelligentTieringPredicateListUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
 	/// <summary>
 	/// IntelligentTieringFilter Unmarshaller 
 	/// </summary>  
-	public class IntelligentTieringPredicateListFilterUnmarshaller : IUnmarshaller<List<IntelligentTieringFilterPredicate>, XmlUnmarshallerContext>, IUnmarshaller<List<IntelligentTieringFilterPredicate>, JsonUnmarshallerContext>
+	public class IntelligentTieringPredicateListFilterUnmarshaller : IXmlUnmarshaller<List<IntelligentTieringFilterPredicate>, XmlUnmarshallerContext>, IXmlUnmarshaller<List<IntelligentTieringFilterPredicate>, JsonUnmarshallerContext>
 	{
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryConfigurationUnmarshaller.cs
index 9eedcc76cc4b..96e074a5dc53 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   InventoryConfiguration Unmarshaller
     /// </summary>
-    public class InventoryConfigurationUnmarshaller : IUnmarshaller<InventoryConfiguration, XmlUnmarshallerContext>, IUnmarshaller<InventoryConfiguration, JsonUnmarshallerContext> 
+    public class InventoryConfigurationUnmarshaller : IXmlUnmarshaller<InventoryConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<InventoryConfiguration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryDestinationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryDestinationUnmarshaller.cs
index 45b60aaddd10..a5c6bb75abeb 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryDestinationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryDestinationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   InventoryDestination Unmarshaller
     /// </summary>
-    public class InventoryDestinationUnmarshaller : IUnmarshaller<InventoryDestination, XmlUnmarshallerContext>, IUnmarshaller<InventoryDestination, JsonUnmarshallerContext> 
+    public class InventoryDestinationUnmarshaller : IXmlUnmarshaller<InventoryDestination, XmlUnmarshallerContext>, IXmlUnmarshaller<InventoryDestination, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryEncryptionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryEncryptionUnmarshaller.cs
index 23618462fa7a..c33141a63fde 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryEncryptionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryEncryptionUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   InventoryEncryption Unmarshaller
     /// </summary>
-    public class InventoryEncryptionUnmarshaller : IUnmarshaller<InventoryEncryption, XmlUnmarshallerContext>, IUnmarshaller<InventoryEncryption, JsonUnmarshallerContext>
+    public class InventoryEncryptionUnmarshaller : IXmlUnmarshaller<InventoryEncryption, XmlUnmarshallerContext>, IXmlUnmarshaller<InventoryEncryption, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryFilterUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryFilterUnmarshaller.cs
index e71caada72bf..ebb6853d743a 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryFilterUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryFilterUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   InventoryFilter Unmarshaller
     /// </summary>
-    public class InventoryFilterUnmarshaller : IUnmarshaller<InventoryFilter, XmlUnmarshallerContext>, IUnmarshaller<InventoryFilter, JsonUnmarshallerContext> 
+    public class InventoryFilterUnmarshaller : IXmlUnmarshaller<InventoryFilter, XmlUnmarshallerContext>, IXmlUnmarshaller<InventoryFilter, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryS3BucketDestinationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryS3BucketDestinationUnmarshaller.cs
index a9c9638d62aa..c46277bbec6e 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryS3BucketDestinationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryS3BucketDestinationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   InventoryS3BucketDestination Unmarshaller
     /// </summary>
-    public class InventoryS3BucketDestinationUnmarshaller : IUnmarshaller<InventoryS3BucketDestination, XmlUnmarshallerContext>, IUnmarshaller<InventoryS3BucketDestination, JsonUnmarshallerContext> 
+    public class InventoryS3BucketDestinationUnmarshaller : IXmlUnmarshaller<InventoryS3BucketDestination, XmlUnmarshallerContext>, IXmlUnmarshaller<InventoryS3BucketDestination, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryScheduleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryScheduleUnmarshaller.cs
index 40d3c0fa158a..24c1ec623828 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryScheduleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/InventoryScheduleUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   InventorySchedule Unmarshaller
     /// </summary>
-    public class InventoryScheduleUnmarshaller : IUnmarshaller<InventorySchedule, XmlUnmarshallerContext>, IUnmarshaller<InventorySchedule, JsonUnmarshallerContext> 
+    public class InventoryScheduleUnmarshaller : IXmlUnmarshaller<InventorySchedule, XmlUnmarshallerContext>, IXmlUnmarshaller<InventorySchedule, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleFilterPredicateListUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleFilterPredicateListUnmarshaller.cs
index 6c2498a5f877..17ce00b66946 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleFilterPredicateListUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleFilterPredicateListUnmarshaller.cs
@@ -22,8 +22,8 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// LifecycleFilterPredicate Unmarshaller
     /// </summary>
-    public class LifecycleFilterPredicateListUnmarshaller : IUnmarshaller<List<LifecycleFilterPredicate>, XmlUnmarshallerContext>,
-        IUnmarshaller<List<LifecycleFilterPredicate>, JsonUnmarshallerContext>
+    public class LifecycleFilterPredicateListUnmarshaller : IXmlUnmarshaller<List<LifecycleFilterPredicate>, XmlUnmarshallerContext>,
+        IXmlUnmarshaller<List<LifecycleFilterPredicate>, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionExpirationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionExpirationUnmarshaller.cs
index e54cf86beb90..e3f3c6b012d1 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionExpirationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionExpirationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   LifecycleRuleNoncurrentVersionExpiration Unmarshaller
     /// </summary>
-    public class LifecycleRuleNoncurrentVersionExpirationUnmarshaller : IUnmarshaller<LifecycleRuleNoncurrentVersionExpiration, XmlUnmarshallerContext>, IUnmarshaller<LifecycleRuleNoncurrentVersionExpiration, JsonUnmarshallerContext>
+    public class LifecycleRuleNoncurrentVersionExpirationUnmarshaller : IXmlUnmarshaller<LifecycleRuleNoncurrentVersionExpiration, XmlUnmarshallerContext>, IXmlUnmarshaller<LifecycleRuleNoncurrentVersionExpiration, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionTransitionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionTransitionUnmarshaller.cs
index ab58a1f44e22..44575e064ff5 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionTransitionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LifecycleRuleNoncurrentVersionTransitionUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   LifecycleRuleNoncurrentVersionTransition Unmarshaller
     /// </summary>
-    public class LifecycleRuleNoncurrentVersionTransitionUnmarshaller : IUnmarshaller<LifecycleRuleNoncurrentVersionTransition, XmlUnmarshallerContext>, IUnmarshaller<LifecycleRuleNoncurrentVersionTransition, JsonUnmarshallerContext>
+    public class LifecycleRuleNoncurrentVersionTransitionUnmarshaller : IXmlUnmarshaller<LifecycleRuleNoncurrentVersionTransition, XmlUnmarshallerContext>, IXmlUnmarshaller<LifecycleRuleNoncurrentVersionTransition, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ListDirectoryBucketsResponseUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ListDirectoryBucketsResponseUnmarshaller.cs
index 9a0270224cb8..1d935238c876 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ListDirectoryBucketsResponseUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ListDirectoryBucketsResponseUnmarshaller.cs
@@ -78,6 +78,29 @@ private static void UnmarshallResult(XmlUnmarshallerContext context, ListDirecto
             return;
         }
 
+
+        /// <summary>
+        /// Unmarshaller error response to exception.
+        /// </summary>  
+        /// <param name="context"></param>
+        /// <param name="innerException"></param>
+        /// <param name="statusCode"></param>
+        /// <returns></returns>
+        public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
+        {
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            errorResponse.InnerException = innerException;
+            errorResponse.StatusCode = statusCode;
+
+            var responseBodyBytes = context.GetResponseBodyBytes();
+
+            using (var streamCopy = new MemoryStream(responseBodyBytes))
+            using (var contextCopy = new XmlUnmarshallerContext(streamCopy, false, null))
+            {
+            }
+            return new AmazonS3Exception(errorResponse.Message, innerException, errorResponse.Type, errorResponse.Code, errorResponse.RequestId, statusCode);
+        }
+
         private static ListDirectoryBucketsResponseUnmarshaller _instance = new ListDirectoryBucketsResponseUnmarshaller();
 
         internal static ListDirectoryBucketsResponseUnmarshaller GetInstance()
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LoggingEnabledUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LoggingEnabledUnmarshaller.cs
index ecd06f437218..729d07c8317f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LoggingEnabledUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/LoggingEnabledUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   LoggingEnabled Unmarshaller
      /// </summary>
-    public class LoggingEnabledUnmarshaller : IUnmarshaller<S3BucketLoggingConfig, XmlUnmarshallerContext>, IUnmarshaller<S3BucketLoggingConfig, JsonUnmarshallerContext> 
+    public class LoggingEnabledUnmarshaller : IXmlUnmarshaller<S3BucketLoggingConfig, XmlUnmarshallerContext>, IXmlUnmarshaller<S3BucketLoggingConfig, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsConfigurationUnmarshaller.cs
index db087ed99b59..ee3023b1170e 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// MetricsConfiguration Unmarshaller 
     /// </summary>   
-    public class MetricsConfigurationUnmarshaller : IUnmarshaller<MetricsConfiguration, XmlUnmarshallerContext>, IUnmarshaller<MetricsConfiguration, JsonUnmarshallerContext> 
+    public class MetricsConfigurationUnmarshaller : IXmlUnmarshaller<MetricsConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<MetricsConfiguration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsPredicateListUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsPredicateListUnmarshaller.cs
index 211821862c7f..76efae93df62 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsPredicateListUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsPredicateListUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// MetricsFilte Unmarshaller 
     /// </summary>  
-    public class MetricsPredicateListFilterUnmarshaller : IUnmarshaller<List<MetricsFilterPredicate>, XmlUnmarshallerContext>, IUnmarshaller<List<MetricsFilterPredicate>, JsonUnmarshallerContext> 
+    public class MetricsPredicateListFilterUnmarshaller : IXmlUnmarshaller<List<MetricsFilterPredicate>, XmlUnmarshallerContext>, IXmlUnmarshaller<List<MetricsFilterPredicate>, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsUnmarshaller.cs
index dfdfc14334c1..a66109d3870c 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MetricsUnmarshaller.cs
@@ -9,7 +9,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Metrics unmarshaller
     /// </summary>
-    public class MetricsUnmarshaller : IUnmarshaller<Metrics, XmlUnmarshallerContext>, IUnmarshaller<Metrics, JsonUnmarshallerContext>
+    public class MetricsUnmarshaller : IXmlUnmarshaller<Metrics, XmlUnmarshallerContext>, IXmlUnmarshaller<Metrics, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MultipartUploadUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MultipartUploadUnmarshaller.cs
index 181726b92173..a152d16ed2e2 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MultipartUploadUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/MultipartUploadUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   UploadsItem Unmarshaller
      /// </summary>
-    public class MultipartUploadUnmarshaller : IUnmarshaller<MultipartUpload, XmlUnmarshallerContext>, IUnmarshaller<MultipartUpload, JsonUnmarshallerContext> 
+    public class MultipartUploadUnmarshaller : IXmlUnmarshaller<MultipartUpload, XmlUnmarshallerContext>, IXmlUnmarshaller<MultipartUpload, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchAccesspointExceptionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchAccesspointExceptionUnmarshaller.cs
index de94930b4ae8..a5ca994ad50d 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchAccesspointExceptionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchAccesspointExceptionUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for NoSuchAccesspointException operation
     /// </summary>  
-    public class NoSuchAccesspointExceptionUnmarshaller : IErrorResponseUnmarshaller<NoSuchAccesspointException, XmlUnmarshallerContext>
+    public class NoSuchAccesspointExceptionUnmarshaller : IXmlErrorResponseUnmarshaller<NoSuchAccesspointException, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchBucketExceptionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchBucketExceptionUnmarshaller.cs
index e0d317334650..1cfc493a086f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchBucketExceptionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/NoSuchBucketExceptionUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for NoSuchBucketException operation
     /// </summary>  
-    public class NoSuchBucketExceptionUnmarshaller : IErrorResponseUnmarshaller<NoSuchBucketException, XmlUnmarshallerContext>
+    public class NoSuchBucketExceptionUnmarshaller : IXmlErrorResponseUnmarshaller<NoSuchBucketException, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockConfigurationUnmarshaller.cs
index ce59812f9b3b..4a6204717d3e 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockConfigurationUnmarshaller.cs
@@ -35,7 +35,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for ObjectLockConfiguration Object
     /// </summary>  
-    public class ObjectLockConfigurationUnmarshaller : IUnmarshaller<ObjectLockConfiguration, XmlUnmarshallerContext>, IUnmarshaller<ObjectLockConfiguration, JsonUnmarshallerContext>
+    public class ObjectLockConfigurationUnmarshaller : IXmlUnmarshaller<ObjectLockConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<ObjectLockConfiguration, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockLegalHoldUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockLegalHoldUnmarshaller.cs
index 45c07ab1093a..d799e0089763 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockLegalHoldUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockLegalHoldUnmarshaller.cs
@@ -35,7 +35,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for ObjectLockLegalHold Object
     /// </summary>  
-    public class ObjectLockLegalHoldUnmarshaller : IUnmarshaller<ObjectLockLegalHold, XmlUnmarshallerContext>, IUnmarshaller<ObjectLockLegalHold, JsonUnmarshallerContext>
+    public class ObjectLockLegalHoldUnmarshaller : IXmlUnmarshaller<ObjectLockLegalHold, XmlUnmarshallerContext>, IXmlUnmarshaller<ObjectLockLegalHold, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRetentionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRetentionUnmarshaller.cs
index 0dd10c644cab..5b91e4890dec 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRetentionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRetentionUnmarshaller.cs
@@ -35,7 +35,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for ObjectLockRetention Object
     /// </summary>  
-    public class ObjectLockRetentionUnmarshaller : IUnmarshaller<ObjectLockRetention, XmlUnmarshallerContext>, IUnmarshaller<ObjectLockRetention, JsonUnmarshallerContext>
+    public class ObjectLockRetentionUnmarshaller : IXmlUnmarshaller<ObjectLockRetention, XmlUnmarshallerContext>, IXmlUnmarshaller<ObjectLockRetention, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRuleUnmarshaller.cs
index a0b85b05812c..4053b224f854 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectLockRuleUnmarshaller.cs
@@ -35,7 +35,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for ObjectLockRule Object
     /// </summary>  
-    public class ObjectLockRuleUnmarshaller : IUnmarshaller<ObjectLockRule, XmlUnmarshallerContext>, IUnmarshaller<ObjectLockRule, JsonUnmarshallerContext>
+    public class ObjectLockRuleUnmarshaller : IXmlUnmarshaller<ObjectLockRule, XmlUnmarshallerContext>, IXmlUnmarshaller<ObjectLockRule, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectPartUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectPartUnmarshaller.cs
index 59a8ef9aaedb..a32320ec964f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectPartUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ObjectPartUnmarshaller.cs
@@ -32,7 +32,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for ObjectPart Object
     /// </summary>  
-    public class ObjectPartUnmarshaller : IUnmarshaller<ObjectPart, XmlUnmarshallerContext>
+    public class ObjectPartUnmarshaller : IXmlUnmarshaller<ObjectPart, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnerUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnerUnmarshaller.cs
index ec3a5e46e950..a13e6706d033 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnerUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnerUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Owner Unmarshaller
      /// </summary>
-    public class OwnerUnmarshaller : IUnmarshaller<Owner, XmlUnmarshallerContext>, IUnmarshaller<Owner, JsonUnmarshallerContext> 
+    public class OwnerUnmarshaller : IXmlUnmarshaller<Owner, XmlUnmarshallerContext>, IXmlUnmarshaller<Owner, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnershipControlsRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnershipControlsRuleUnmarshaller.cs
index 350fe38d481f..318e19e6e5be 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnershipControlsRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/OwnershipControlsRuleUnmarshaller.cs
@@ -25,7 +25,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// OwnershipControlsRule unmarshaller
     /// </summary>
-    public class OwnershipControlsRuleUnmarshaller : IUnmarshaller<OwnershipControlsRule, XmlUnmarshallerContext>, IUnmarshaller<OwnershipControlsRule, JsonUnmarshallerContext>
+    public class OwnershipControlsRuleUnmarshaller : IXmlUnmarshaller<OwnershipControlsRule, XmlUnmarshallerContext>, IXmlUnmarshaller<OwnershipControlsRule, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartDetailUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartDetailUnmarshaller.cs
index 27d644ace4dd..628469c2d86a 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartDetailUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartDetailUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   PartsItem Unmarshaller
      /// </summary>
-    public class PartDetailUnmarshaller : IUnmarshaller<PartDetail, XmlUnmarshallerContext>, IUnmarshaller<PartDetail, JsonUnmarshallerContext> 
+    public class PartDetailUnmarshaller : IXmlUnmarshaller<PartDetail, XmlUnmarshallerContext>, IXmlUnmarshaller<PartDetail, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartitionedPrefixUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartitionedPrefixUnmarshaller.cs
index d2e87fd529ad..f4f925e70937 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartitionedPrefixUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PartitionedPrefixUnmarshaller.cs
@@ -19,7 +19,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for PartitionedPrefix Object
     /// </summary>  
-    public class PartitionedPrefixUnmarshaller : IUnmarshaller<PartitionedPrefix, XmlUnmarshallerContext>, IUnmarshaller<PartitionedPrefix, JsonUnmarshallerContext>
+    public class PartitionedPrefixUnmarshaller : IXmlUnmarshaller<PartitionedPrefix, XmlUnmarshallerContext>, IXmlUnmarshaller<PartitionedPrefix, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PolicyStatusUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PolicyStatusUnmarshaller.cs
index 1de7488e9fba..e43bb534a9bc 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PolicyStatusUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PolicyStatusUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      /// PolicyStatus Unmarshaller
      /// </summary>
-    public class PolicyStatusUnmarshaller : IUnmarshaller<PolicyStatus, XmlUnmarshallerContext>, IUnmarshaller<PolicyStatus, JsonUnmarshallerContext> 
+    public class PolicyStatusUnmarshaller : IXmlUnmarshaller<PolicyStatus, XmlUnmarshallerContext>, IXmlUnmarshaller<PolicyStatus, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PublicBlockConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PublicBlockConfigurationUnmarshaller.cs
index 0b40ca9a2e37..fa57643e7aa8 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PublicBlockConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PublicBlockConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      /// PublicAccessBlockConfiguration Unmarshaller
      /// </summary>
-    public class PublicAccessBlockConfigurationUnmarshaller : IUnmarshaller<PublicAccessBlockConfiguration, XmlUnmarshallerContext>, IUnmarshaller<PublicAccessBlockConfiguration, JsonUnmarshallerContext> 
+    public class PublicAccessBlockConfigurationUnmarshaller : IXmlUnmarshaller<PublicAccessBlockConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<PublicAccessBlockConfiguration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PutBucketResponseUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PutBucketResponseUnmarshaller.cs
index d30e4e78808c..c59458987f9b 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PutBucketResponseUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/PutBucketResponseUnmarshaller.cs
@@ -50,7 +50,7 @@ public override AmazonWebServiceResponse Unmarshall(XmlUnmarshallerContext conte
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(XmlUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = S3ErrorResponseUnmarshaller.Instance.Unmarshall(context);
+            ErrorResponse errorResponse = XmlErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/QueueConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/QueueConfigurationUnmarshaller.cs
index 3a7a77411456..d0351036632d 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/QueueConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/QueueConfigurationUnmarshaller.cs
@@ -24,7 +24,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// QueueConfiguration unmarshaller
     /// </summary>
-    public class QueueConfigurationUnmarshaller : IUnmarshaller<QueueConfiguration, XmlUnmarshallerContext>, IUnmarshaller<QueueConfiguration, JsonUnmarshallerContext> 
+    public class QueueConfigurationUnmarshaller : IXmlUnmarshaller<QueueConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<QueueConfiguration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicaModificationsUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicaModificationsUnmarshaller.cs
index 589c4382979b..cc58c004e24a 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicaModificationsUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicaModificationsUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Unmarshaller for ReplicaModifications
     /// </summary>
-    public class ReplicaModificationsUnmarshaller : IUnmarshaller<ReplicaModifications, XmlUnmarshallerContext>, IUnmarshaller<ReplicaModifications, JsonUnmarshallerContext>
+    public class ReplicaModificationsUnmarshaller : IXmlUnmarshaller<ReplicaModifications, XmlUnmarshallerContext>, IXmlUnmarshaller<ReplicaModifications, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationDestinationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationDestinationUnmarshaller.cs
index c9670c472e50..84d211d5a802 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationDestinationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationDestinationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ReplicationDestination unmarshaller
     /// </summary>
-    public class ReplicationDestinationUnmarshaller : IUnmarshaller<ReplicationDestination, XmlUnmarshallerContext>, IUnmarshaller<ReplicationDestination, JsonUnmarshallerContext>
+    public class ReplicationDestinationUnmarshaller : IXmlUnmarshaller<ReplicationDestination, XmlUnmarshallerContext>, IXmlUnmarshaller<ReplicationDestination, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleAndOperatorUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleAndOperatorUnmarshaller.cs
index ad8df90d8d28..cdb18cc538aa 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleAndOperatorUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleAndOperatorUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ReplicationRuleAndOperator unmarshaller
     /// </summary>
-    public class ReplicationRuleAndOperatorUnmarshaller : IUnmarshaller<ReplicationRuleAndOperator, XmlUnmarshallerContext>
+    public class ReplicationRuleAndOperatorUnmarshaller : IXmlUnmarshaller<ReplicationRuleAndOperator, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleFilterUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleFilterUnmarshaller.cs
index 780de7cc1127..e23001489b65 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleFilterUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleFilterUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ReplicationRuleFilter unmarshaller
     /// </summary>
-    public class ReplicationRuleFilterUnmarshaller : IUnmarshaller<ReplicationRuleFilter, XmlUnmarshallerContext>
+    public class ReplicationRuleFilterUnmarshaller : IXmlUnmarshaller<ReplicationRuleFilter, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleUnmarshaller.cs
index 3a2ef0f5458e..d3ecd82e4f90 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationRuleUnmarshaller.cs
@@ -23,7 +23,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ReplicationRule unmarshaller
     /// </summary>
-    public class ReplicationRuleUnmarshaller : IUnmarshaller<ReplicationRule, XmlUnmarshallerContext>, IUnmarshaller<ReplicationRule, JsonUnmarshallerContext> 
+    public class ReplicationRuleUnmarshaller : IXmlUnmarshaller<ReplicationRule, XmlUnmarshallerContext>, IXmlUnmarshaller<ReplicationRule, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeUnmarshaller.cs
index c4769fc83f73..0234aa902436 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeUnmarshaller.cs
@@ -9,7 +9,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ReplicationTime unmarshaller
     /// </summary>
-    public class ReplicationTimeUnmarshaller : IUnmarshaller<ReplicationTime, XmlUnmarshallerContext>, IUnmarshaller<ReplicationTime, JsonUnmarshallerContext>
+    public class ReplicationTimeUnmarshaller : IXmlUnmarshaller<ReplicationTime, XmlUnmarshallerContext>, IXmlUnmarshaller<ReplicationTime, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeValueUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeValueUnmarshaller.cs
index 29901c18eb5e..09a6e30e0724 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeValueUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ReplicationTimeValueUnmarshaller.cs
@@ -9,7 +9,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ReplicationTimeValue unmarshaller
     /// </summary>
-    public class ReplicationTimeValueUnmarshaller : IUnmarshaller<ReplicationTimeValue, XmlUnmarshallerContext>, IUnmarshaller<ReplicationTimeValue, JsonUnmarshallerContext>
+    public class ReplicationTimeValueUnmarshaller : IXmlUnmarshaller<ReplicationTimeValue, XmlUnmarshallerContext>, IXmlUnmarshaller<ReplicationTimeValue, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RestoreStatusUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RestoreStatusUnmarshaller.cs
index b658ed0f6a55..d2563edddf95 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RestoreStatusUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RestoreStatusUnmarshaller.cs
@@ -9,7 +9,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for RestoreStatus Object
     /// </summary>  
-    public class RestoreStatusUnmarshaller : IUnmarshaller<RestoreStatus, XmlUnmarshallerContext>
+    public class RestoreStatusUnmarshaller : IXmlUnmarshaller<RestoreStatus, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshall the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleConditionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleConditionUnmarshaller.cs
index 52ba68dc831f..2024b694c373 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleConditionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleConditionUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Condition Unmarshaller
      /// </summary>
-    public class RoutingRuleConditionUnmarshaller : IUnmarshaller<RoutingRuleCondition, XmlUnmarshallerContext>, IUnmarshaller<RoutingRuleCondition, JsonUnmarshallerContext> 
+    public class RoutingRuleConditionUnmarshaller : IXmlUnmarshaller<RoutingRuleCondition, XmlUnmarshallerContext>, IXmlUnmarshaller<RoutingRuleCondition, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleRedirectUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleRedirectUnmarshaller.cs
index aa9bcb7501db..d23e733b4c8e 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleRedirectUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleRedirectUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Redirect Unmarshaller
      /// </summary>
-    public class RoutingRuleRedirectUnmarshaller : IUnmarshaller<RoutingRuleRedirect, XmlUnmarshallerContext>, IUnmarshaller<RoutingRuleRedirect, JsonUnmarshallerContext> 
+    public class RoutingRuleRedirectUnmarshaller : IXmlUnmarshaller<RoutingRuleRedirect, XmlUnmarshallerContext>, IXmlUnmarshaller<RoutingRuleRedirect, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleUnmarshaller.cs
index 371a1d2cde0d..8d3a4186522c 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RoutingRuleUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   RoutingRule Unmarshaller
      /// </summary>
-    public class RoutingRuleUnmarshaller : IUnmarshaller<RoutingRule, XmlUnmarshallerContext>, IUnmarshaller<RoutingRule, JsonUnmarshallerContext> 
+    public class RoutingRuleUnmarshaller : IXmlUnmarshaller<RoutingRule, XmlUnmarshallerContext>, IXmlUnmarshaller<RoutingRule, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RulesItemUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RulesItemUnmarshaller.cs
index d2c2737b5914..3466974e616f 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RulesItemUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/RulesItemUnmarshaller.cs
@@ -25,7 +25,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   RulesItem Unmarshaller
      /// </summary>
-    public class RulesItemUnmarshaller : IUnmarshaller<LifecycleRule, XmlUnmarshallerContext>, IUnmarshaller<LifecycleRule, JsonUnmarshallerContext> 
+    public class RulesItemUnmarshaller : IXmlUnmarshaller<LifecycleRule, XmlUnmarshallerContext>, IXmlUnmarshaller<LifecycleRule, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3ErrorResponseUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3ErrorResponseUnmarshaller.cs
index d1f7c70dcbe1..e544d9405868 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3ErrorResponseUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3ErrorResponseUnmarshaller.cs
@@ -28,7 +28,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///    Response Unmarshaller for all Errors
     /// </summary>
-    public class S3ErrorResponseUnmarshaller : IUnmarshaller<S3ErrorResponse, XmlUnmarshallerContext>
+    public class S3ErrorResponseUnmarshaller : IXmlUnmarshaller<S3ErrorResponse, XmlUnmarshallerContext>
     {
         const string XML_CONTENT_TYPE = "text/xml";
 
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3KeyFilterUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3KeyFilterUnmarshaller.cs
index 53fe304a0db8..8e123e8c2fef 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3KeyFilterUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/S3KeyFilterUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   S3KeyFilter Unmarshaller
     /// </summary>
-    public class S3KeyFilterUnmarshaller : IUnmarshaller<S3KeyFilter, XmlUnmarshallerContext>, IUnmarshaller<S3KeyFilter, JsonUnmarshallerContext> 
+    public class S3KeyFilterUnmarshaller : IXmlUnmarshaller<S3KeyFilter, XmlUnmarshallerContext>, IXmlUnmarshaller<S3KeyFilter, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSEKMSUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSEKMSUnmarshaller.cs
index 3ea749ca0db8..7d70df6db02c 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSEKMSUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSEKMSUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///   SSEKMS Unmarshaller
     /// </summary>
-    public class SSEKMSUnmarshaller : IUnmarshaller<SSEKMS, XmlUnmarshallerContext>, IUnmarshaller<SSEKMS, JsonUnmarshallerContext>
+    public class SSEKMSUnmarshaller : IXmlUnmarshaller<SSEKMS, XmlUnmarshallerContext>, IXmlUnmarshaller<SSEKMS, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSES3Unmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSES3Unmarshaller.cs
index a6a480995bfa..03f90edd38ba 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSES3Unmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SSES3Unmarshaller.cs
@@ -20,7 +20,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// SSES3 Unmarshaller
     /// </summary>
-    public class SSES3Unmarshaller : IUnmarshaller<SSES3, XmlUnmarshallerContext>, IUnmarshaller<SSES3, JsonUnmarshallerContext>
+    public class SSES3Unmarshaller : IXmlUnmarshaller<SSES3, XmlUnmarshallerContext>, IXmlUnmarshaller<SSES3, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionByDefaultUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionByDefaultUnmarshaller.cs
index 199df5a01329..a5feeeda21a0 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionByDefaultUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionByDefaultUnmarshaller.cs
@@ -23,7 +23,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ServerSideEncryptionByDefault unmarshaller
     /// </summary>
-    public class ServerSideEncryptionByDefaultUnmarshaller : IUnmarshaller<ServerSideEncryptionByDefault, XmlUnmarshallerContext>, IUnmarshaller<ServerSideEncryptionByDefault, JsonUnmarshallerContext>
+    public class ServerSideEncryptionByDefaultUnmarshaller : IXmlUnmarshaller<ServerSideEncryptionByDefault, XmlUnmarshallerContext>, IXmlUnmarshaller<ServerSideEncryptionByDefault, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionRuleUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionRuleUnmarshaller.cs
index d767c87f1fd6..8326f74b8df7 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionRuleUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/ServerSideEncryptionRuleUnmarshaller.cs
@@ -24,7 +24,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// ServerSideEncryptionRule unmarshaller
     /// </summary>
-    public class ServerSideEncryptionRuleUnmarshaller : IUnmarshaller<ServerSideEncryptionRule, XmlUnmarshallerContext>, IUnmarshaller<ServerSideEncryptionRule, JsonUnmarshallerContext>
+    public class ServerSideEncryptionRuleUnmarshaller : IXmlUnmarshaller<ServerSideEncryptionRule, XmlUnmarshallerContext>, IXmlUnmarshaller<ServerSideEncryptionRule, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SessionCredentialsUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SessionCredentialsUnmarshaller.cs
index 3a2ee3515c17..c4b6dd774343 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SessionCredentialsUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SessionCredentialsUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for SessionCredentials Object
     /// </summary>  
-    public class SessionCredentialsUnmarshaller : IUnmarshaller<SessionCredentials, XmlUnmarshallerContext>
+    public class SessionCredentialsUnmarshaller : IXmlUnmarshaller<SessionCredentials, XmlUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SimplePrefixUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SimplePrefixUnmarshaller.cs
index 882b3d525f21..3d4b269f696a 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SimplePrefixUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SimplePrefixUnmarshaller.cs
@@ -19,7 +19,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for SimplePrefix Object
     /// </summary>  
-    public class SimplePrefixUnmarshaller : IUnmarshaller<SimplePrefix, XmlUnmarshallerContext>, IUnmarshaller<SimplePrefix, JsonUnmarshallerContext>
+    public class SimplePrefixUnmarshaller : IXmlUnmarshaller<SimplePrefix, XmlUnmarshallerContext>, IXmlUnmarshaller<SimplePrefix, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SourceSelectionCriteriaUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SourceSelectionCriteriaUnmarshaller.cs
index 29fc8503cab1..b772932fcfe1 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SourceSelectionCriteriaUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SourceSelectionCriteriaUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// SourceSelectionCriteria unmarshaller
     /// </summary>
-    public class SourceSelectionCriteriaUnmarshaller : IUnmarshaller<SourceSelectionCriteria, XmlUnmarshallerContext>, IUnmarshaller<SourceSelectionCriteria, JsonUnmarshallerContext>
+    public class SourceSelectionCriteriaUnmarshaller : IXmlUnmarshaller<SourceSelectionCriteria, XmlUnmarshallerContext>, IXmlUnmarshaller<SourceSelectionCriteria, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SseKmsEncryptedObjectsUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SseKmsEncryptedObjectsUnmarshaller.cs
index b868722b5b7d..30201e98d236 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SseKmsEncryptedObjectsUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/SseKmsEncryptedObjectsUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// SseKmsEncryptedObjects unmarshaller
     /// </summary>
-    public class SseKmsEncryptedObjectsUnmarshaller : IUnmarshaller<SseKmsEncryptedObjects, XmlUnmarshallerContext>, IUnmarshaller<SseKmsEncryptedObjects, JsonUnmarshallerContext>
+    public class SseKmsEncryptedObjectsUnmarshaller : IXmlUnmarshaller<SseKmsEncryptedObjects, XmlUnmarshallerContext>, IXmlUnmarshaller<SseKmsEncryptedObjects, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisDataExportUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisDataExportUnmarshaller.cs
index 714c576a9376..86e5dc6380fc 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisDataExportUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisDataExportUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// StorageClassAnalysisDataExportDataExportUnmarshaller
     /// </summary>
-    public class StorageClassAnalysisDataExportUnmarshaller : IUnmarshaller<StorageClassAnalysisDataExport, XmlUnmarshallerContext>, IUnmarshaller<StorageClassAnalysisDataExport, JsonUnmarshallerContext>
+    public class StorageClassAnalysisDataExportUnmarshaller : IXmlUnmarshaller<StorageClassAnalysisDataExport, XmlUnmarshallerContext>, IXmlUnmarshaller<StorageClassAnalysisDataExport, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisUnmarshaller.cs
index 6e9c960f9647..00ed705e2666 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/StorageClassAnalysisUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     ///  StorageClassAnalysisUnmarshaller
     /// </summary>
-    public class StorageClassAnalysisUnmarshaller : IUnmarshaller<StorageClassAnalysis, XmlUnmarshallerContext>, IUnmarshaller<StorageClassAnalysis, JsonUnmarshallerContext>
+    public class StorageClassAnalysisUnmarshaller : IXmlUnmarshaller<StorageClassAnalysis, XmlUnmarshallerContext>, IXmlUnmarshaller<StorageClassAnalysis, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TagUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TagUnmarshaller.cs
index a5156ab67632..08827be36e1d 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TagUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TagUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Tag Unmarshaller
      /// </summary>
-    public class TagUnmarshaller : IUnmarshaller<Tag, XmlUnmarshallerContext>, IUnmarshaller<Tag, JsonUnmarshallerContext> 
+    public class TagUnmarshaller : IXmlUnmarshaller<Tag, XmlUnmarshallerContext>, IXmlUnmarshaller<Tag, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TargetObjectKeyFormatUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TargetObjectKeyFormatUnmarshaller.cs
index 915f53c0eba4..72ae0f5f4ad9 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TargetObjectKeyFormatUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TargetObjectKeyFormatUnmarshaller.cs
@@ -19,7 +19,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
     /// <summary>
     /// Response Unmarshaller for TargetObjectKeyFormat Object
     /// </summary>  
-    public class TargetObjectKeyFormatUnmarshaller : IUnmarshaller<TargetObjectKeyFormat, XmlUnmarshallerContext>, IUnmarshaller<TargetObjectKeyFormat, JsonUnmarshallerContext>
+    public class TargetObjectKeyFormatUnmarshaller : IXmlUnmarshaller<TargetObjectKeyFormat, XmlUnmarshallerContext>, IXmlUnmarshaller<TargetObjectKeyFormat, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TieringUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TieringUnmarshaller.cs
index f4463e300432..fd9313e48d9e 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TieringUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TieringUnmarshaller.cs
@@ -24,7 +24,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
 	/// <summary>
 	///   Tiering Unmarshaller
 	/// </summary>
-	public class TieringUnmarshaller : IUnmarshaller<Tiering, XmlUnmarshallerContext>, IUnmarshaller<Tiering, JsonUnmarshallerContext>
+	public class TieringUnmarshaller : IXmlUnmarshaller<Tiering, XmlUnmarshallerContext>, IXmlUnmarshaller<Tiering, JsonUnmarshallerContext>
 	{
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TopicConfigurationUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TopicConfigurationUnmarshaller.cs
index 54fae6646be7..4ae52e4b955c 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TopicConfigurationUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TopicConfigurationUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   TopicConfiguration Unmarshaller
      /// </summary>
-    public class TopicConfigurationUnmarshaller : IUnmarshaller<TopicConfiguration, XmlUnmarshallerContext>, IUnmarshaller<TopicConfiguration, JsonUnmarshallerContext> 
+    public class TopicConfigurationUnmarshaller : IXmlUnmarshaller<TopicConfiguration, XmlUnmarshallerContext>, IXmlUnmarshaller<TopicConfiguration, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TransitionUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TransitionUnmarshaller.cs
index 7c2d26086f33..7f5bc47ad275 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TransitionUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/TransitionUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   Transition Unmarshaller
      /// </summary>
-    public class TransitionUnmarshaller : IUnmarshaller<LifecycleTransition, XmlUnmarshallerContext>, IUnmarshaller<LifecycleTransition, JsonUnmarshallerContext> 
+    public class TransitionUnmarshaller : IXmlUnmarshaller<LifecycleTransition, XmlUnmarshallerContext>, IXmlUnmarshaller<LifecycleTransition, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/VersionsItemUnmarshaller.cs b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/VersionsItemUnmarshaller.cs
index 05e0a92bae7d..b2274347e2e1 100644
--- a/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/VersionsItemUnmarshaller.cs
+++ b/sdk/src/Services/S3/Custom/Model/Internal/MarshallTransformations/VersionsItemUnmarshaller.cs
@@ -22,7 +22,7 @@ namespace Amazon.S3.Model.Internal.MarshallTransformations
      /// <summary>
      ///   VersionsItem Unmarshaller
      /// </summary>
-    public class VersionsItemUnmarshaller : IUnmarshaller<S3ObjectVersion, XmlUnmarshallerContext>, IUnmarshaller<S3ObjectVersion, JsonUnmarshallerContext> 
+    public class VersionsItemUnmarshaller : IXmlUnmarshaller<S3ObjectVersion, XmlUnmarshallerContext>, IXmlUnmarshaller<S3ObjectVersion, JsonUnmarshallerContext> 
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionRequestMarshaller.cs
index 10ac2b387bcd..8a91717355f1 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,54 +64,59 @@ public IRequest Marshall(AddPermissionRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetActions())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("Actions");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestActionsListValue in publicRequest.Actions)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetActions())
-                    {
-                        context.Writer.WritePropertyName("Actions");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestActionsListValue in publicRequest.Actions)
-                        {
-                                context.Writer.Write(publicRequestActionsListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
-
-                    if(publicRequest.IsSetAWSAccountIds())
-                    {
-                        context.Writer.WritePropertyName("AWSAccountIds");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestAWSAccountIdsListValue in publicRequest.AWSAccountIds)
-                        {
-                                context.Writer.Write(publicRequestAWSAccountIdsListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
-
-                    if(publicRequest.IsSetLabel())
-                    {
-                        context.Writer.WritePropertyName("Label");
-                        context.Writer.Write(publicRequest.Label);
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
+                        context.Writer.WriteStringValue(publicRequestActionsListValue);
+                }
+                context.Writer.WriteEndArray();
+            }
 
-                    writer.WriteObjectEnd();
+            if(publicRequest.IsSetAWSAccountIds())
+            {
+                context.Writer.WritePropertyName("AWSAccountIds");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestAWSAccountIdsListValue in publicRequest.AWSAccountIds)
+                {
+                        context.Writer.WriteStringValue(publicRequestAWSAccountIdsListValue);
                 }
+                context.Writer.WriteEndArray();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetLabel())
+            {
+                context.Writer.WritePropertyName("Label");
+                context.Writer.WriteStringValue(publicRequest.Label);
             }
 
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
+            }
+
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionResponseUnmarshaller.cs
index 364f7a428451..c81c02e741f3 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/AddPermissionResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             AddPermissionResponse response = new AddPermissionResponse();
 
-
             return response;
         }
 
@@ -61,39 +60,40 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("OverLimit"))
                 {
-                    return OverLimitExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return OverLimitExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchEntryIdsNotDistinctExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchEntryIdsNotDistinctExceptionUnmarshaller.cs
index 8d7fd3f10303..308b36e19395 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchEntryIdsNotDistinctExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchEntryIdsNotDistinctExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for BatchEntryIdsNotDistinctException Object
     /// </summary>  
-    public class BatchEntryIdsNotDistinctExceptionUnmarshaller : IErrorResponseUnmarshaller<BatchEntryIdsNotDistinctException, JsonUnmarshallerContext>
+    public class BatchEntryIdsNotDistinctExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<BatchEntryIdsNotDistinctException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public BatchEntryIdsNotDistinctException Unmarshall(JsonUnmarshallerContext context)
+        public BatchEntryIdsNotDistinctException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public BatchEntryIdsNotDistinctException Unmarshall(JsonUnmarshallerContext cont
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public BatchEntryIdsNotDistinctException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public BatchEntryIdsNotDistinctException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public BatchEntryIdsNotDistinctException Unmarshall(JsonUnmarshallerContext cont
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchRequestTooLongExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchRequestTooLongExceptionUnmarshaller.cs
index f0f3bfac78d3..7502980833ff 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchRequestTooLongExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchRequestTooLongExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for BatchRequestTooLongException Object
     /// </summary>  
-    public class BatchRequestTooLongExceptionUnmarshaller : IErrorResponseUnmarshaller<BatchRequestTooLongException, JsonUnmarshallerContext>
+    public class BatchRequestTooLongExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<BatchRequestTooLongException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public BatchRequestTooLongException Unmarshall(JsonUnmarshallerContext context)
+        public BatchRequestTooLongException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public BatchRequestTooLongException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public BatchRequestTooLongException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public BatchRequestTooLongException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public BatchRequestTooLongException Unmarshall(JsonUnmarshallerContext context,
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchResultErrorEntryUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchResultErrorEntryUnmarshaller.cs
index 8af49700754c..ef15f5beee58 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchResultErrorEntryUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/BatchResultErrorEntryUnmarshaller.cs
@@ -29,65 +29,55 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for BatchResultErrorEntry Object
     /// </summary>  
-    public class BatchResultErrorEntryUnmarshaller : IUnmarshaller<BatchResultErrorEntry, XmlUnmarshallerContext>, IUnmarshaller<BatchResultErrorEntry, JsonUnmarshallerContext>
+    public class BatchResultErrorEntryUnmarshaller : IJsonUnmarshaller<BatchResultErrorEntry, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        BatchResultErrorEntry IUnmarshaller<BatchResultErrorEntry, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public BatchResultErrorEntry Unmarshall(JsonUnmarshallerContext context)
+        public BatchResultErrorEntry Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             BatchResultErrorEntry unmarshalledObject = new BatchResultErrorEntry();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Code", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Code = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Code = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Id", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Id = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Id = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Message", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Message = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Message = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("SenderFault", targetDepth))
                 {
                     var unmarshaller = NullableBoolUnmarshaller.Instance;
-                    unmarshalledObject.SenderFault = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.SenderFault = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskRequestMarshaller.cs
index bdad504a48df..01f5710efffd 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,26 +64,31 @@ public IRequest Marshall(CancelMessageMoveTaskRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetTaskHandle())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetTaskHandle())
-                    {
-                        context.Writer.WritePropertyName("TaskHandle");
-                        context.Writer.Write(publicRequest.TaskHandle);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WritePropertyName("TaskHandle");
+                context.Writer.WriteStringValue(publicRequest.TaskHandle);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskResponseUnmarshaller.cs
index 115817fea0d5..b89dddc1bcaf 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CancelMessageMoveTaskResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class CancelMessageMoveTaskResponseUnmarshaller : JsonResponseUnmarshalle
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             CancelMessageMoveTaskResponse response = new CancelMessageMoveTaskResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("ApproximateNumberOfMessagesMoved", targetDepth))
                 {
                     var unmarshaller = NullableLongUnmarshaller.Instance;
-                    response.ApproximateNumberOfMessagesMoved = unmarshaller.Unmarshall(context);
+                    response.ApproximateNumberOfMessagesMoved = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,35 +72,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("ResourceNotFoundException"))
                 {
-                    return ResourceNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return ResourceNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestEntryMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestEntryMarshaller.cs
index 049e188ab69f..e1a8b6a30ce0 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestEntryMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestEntryMarshaller.cs
@@ -28,8 +28,6 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -51,19 +49,19 @@ public void Marshall(ChangeMessageVisibilityBatchRequestEntry requestObject, Jso
             if(requestObject.IsSetId())
             {
                 context.Writer.WritePropertyName("Id");
-                context.Writer.Write(requestObject.Id);
+                context.Writer.WriteStringValue(requestObject.Id);
             }
 
             if(requestObject.IsSetReceiptHandle())
             {
                 context.Writer.WritePropertyName("ReceiptHandle");
-                context.Writer.Write(requestObject.ReceiptHandle);
+                context.Writer.WriteStringValue(requestObject.ReceiptHandle);
             }
 
             if(requestObject.IsSetVisibilityTimeout())
             {
                 context.Writer.WritePropertyName("VisibilityTimeout");
-                context.Writer.Write(requestObject.VisibilityTimeout.Value);
+                context.Writer.WriteNumberValue(requestObject.VisibilityTimeout.Value);
             }
 
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestMarshaller.cs
index d7d423711cc0..d15d784413a2 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,42 +64,47 @@ public IRequest Marshall(ChangeMessageVisibilityBatchRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetEntries())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("Entries");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestEntriesListValue in publicRequest.Entries)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetEntries())
-                    {
-                        context.Writer.WritePropertyName("Entries");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestEntriesListValue in publicRequest.Entries)
-                        {
-                            context.Writer.WriteObjectStart();
-
-                            var marshaller = ChangeMessageVisibilityBatchRequestEntryMarshaller.Instance;
-                            marshaller.Marshall(publicRequestEntriesListValue, context);
-
-                            context.Writer.WriteObjectEnd();
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
+                    context.Writer.WriteStartObject();
 
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
+                    var marshaller = ChangeMessageVisibilityBatchRequestEntryMarshaller.Instance;
+                    marshaller.Marshall(publicRequestEntriesListValue, context);
 
-                    writer.WriteObjectEnd();
+                    context.Writer.WriteEndObject();
                 }
+                context.Writer.WriteEndArray();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResponseUnmarshaller.cs
index 0f24bbb030ce..7684bfdc5c35 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,21 +47,21 @@ public class ChangeMessageVisibilityBatchResponseUnmarshaller : JsonResponseUnma
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             ChangeMessageVisibilityBatchResponse response = new ChangeMessageVisibilityBatchResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Failed", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<BatchResultErrorEntry, BatchResultErrorEntryUnmarshaller>(BatchResultErrorEntryUnmarshaller.Instance);
-                    response.Failed = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<BatchResultErrorEntry, BatchResultErrorEntryUnmarshaller>(BatchResultErrorEntryUnmarshaller.Instance);
+                    response.Failed = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Successful", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<ChangeMessageVisibilityBatchResultEntry, ChangeMessageVisibilityBatchResultEntryUnmarshaller>(ChangeMessageVisibilityBatchResultEntryUnmarshaller.Instance);
-                    response.Successful = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<ChangeMessageVisibilityBatchResultEntry, ChangeMessageVisibilityBatchResultEntryUnmarshaller>(ChangeMessageVisibilityBatchResultEntryUnmarshaller.Instance);
+                    response.Successful = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -78,51 +78,52 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("BatchEntryIdsNotDistinct"))
                 {
-                    return BatchEntryIdsNotDistinctExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return BatchEntryIdsNotDistinctExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("EmptyBatchRequest"))
                 {
-                    return EmptyBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return EmptyBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidBatchEntryId"))
                 {
-                    return InvalidBatchEntryIdExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidBatchEntryIdExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("TooManyEntriesInBatchRequest"))
                 {
-                    return TooManyEntriesInBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return TooManyEntriesInBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResultEntryUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResultEntryUnmarshaller.cs
index e98c9e8c4dd6..5daa661cfcb2 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResultEntryUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityBatchResultEntryUnmarshaller.cs
@@ -29,47 +29,37 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for ChangeMessageVisibilityBatchResultEntry Object
     /// </summary>  
-    public class ChangeMessageVisibilityBatchResultEntryUnmarshaller : IUnmarshaller<ChangeMessageVisibilityBatchResultEntry, XmlUnmarshallerContext>, IUnmarshaller<ChangeMessageVisibilityBatchResultEntry, JsonUnmarshallerContext>
+    public class ChangeMessageVisibilityBatchResultEntryUnmarshaller : IJsonUnmarshaller<ChangeMessageVisibilityBatchResultEntry, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        ChangeMessageVisibilityBatchResultEntry IUnmarshaller<ChangeMessageVisibilityBatchResultEntry, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public ChangeMessageVisibilityBatchResultEntry Unmarshall(JsonUnmarshallerContext context)
+        public ChangeMessageVisibilityBatchResultEntry Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             ChangeMessageVisibilityBatchResultEntry unmarshalledObject = new ChangeMessageVisibilityBatchResultEntry();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Id", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Id = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Id = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityRequestMarshaller.cs
index b673acfab648..1022b447bb43 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,38 +64,43 @@ public IRequest Marshall(ChangeMessageVisibilityRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    if(publicRequest.IsSetReceiptHandle())
-                    {
-                        context.Writer.WritePropertyName("ReceiptHandle");
-                        context.Writer.Write(publicRequest.ReceiptHandle);
-                    }
-
-                    if(publicRequest.IsSetVisibilityTimeout())
-                    {
-                        context.Writer.WritePropertyName("VisibilityTimeout");
-                        context.Writer.Write(publicRequest.VisibilityTimeout.Value);
-                    }
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
+            }
 
-                    writer.WriteObjectEnd();
-                }
+            if(publicRequest.IsSetReceiptHandle())
+            {
+                context.Writer.WritePropertyName("ReceiptHandle");
+                context.Writer.WriteStringValue(publicRequest.ReceiptHandle);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetVisibilityTimeout())
+            {
+                context.Writer.WritePropertyName("VisibilityTimeout");
+                context.Writer.WriteNumberValue(publicRequest.VisibilityTimeout.Value);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityResponseUnmarshaller.cs
index 2d7008d8d2fe..2ddc4088d45d 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ChangeMessageVisibilityResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             ChangeMessageVisibilityResponse response = new ChangeMessageVisibilityResponse();
 
-
             return response;
         }
 
@@ -61,43 +60,44 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("MessageNotInflight"))
                 {
-                    return MessageNotInflightExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return MessageNotInflightExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("ReceiptHandleIsInvalid"))
                 {
-                    return ReceiptHandleIsInvalidExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return ReceiptHandleIsInvalidExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueRequestMarshaller.cs
index 9efe0efbec4c..c8610a0b1bf2 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,54 +64,59 @@ public IRequest Marshall(CreateQueueRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetAttributes())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("Attributes");
+                context.Writer.WriteStartObject();
+                foreach (var publicRequestAttributesKvp in publicRequest.Attributes)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetAttributes())
-                    {
-                        context.Writer.WritePropertyName("Attributes");
-                        context.Writer.WriteObjectStart();
-                        foreach (var publicRequestAttributesKvp in publicRequest.Attributes)
-                        {
-                            context.Writer.WritePropertyName(publicRequestAttributesKvp.Key);
-                            var publicRequestAttributesValue = publicRequestAttributesKvp.Value;
-
-                                context.Writer.Write(publicRequestAttributesValue);
-                        }
-                        context.Writer.WriteObjectEnd();
-                    }
+                    context.Writer.WritePropertyName(publicRequestAttributesKvp.Key);
+                    var publicRequestAttributesValue = publicRequestAttributesKvp.Value;
 
-                    if(publicRequest.IsSetQueueName())
-                    {
-                        context.Writer.WritePropertyName("QueueName");
-                        context.Writer.Write(publicRequest.QueueName);
-                    }
+                        context.Writer.WriteStringValue(publicRequestAttributesValue);
+                }
+                context.Writer.WriteEndObject();
+            }
 
-                    if(publicRequest.IsSetTags())
-                    {
-                        context.Writer.WritePropertyName("tags");
-                        context.Writer.WriteObjectStart();
-                        foreach (var publicRequestTagsKvp in publicRequest.Tags)
-                        {
-                            context.Writer.WritePropertyName(publicRequestTagsKvp.Key);
-                            var publicRequestTagsValue = publicRequestTagsKvp.Value;
+            if(publicRequest.IsSetQueueName())
+            {
+                context.Writer.WritePropertyName("QueueName");
+                context.Writer.WriteStringValue(publicRequest.QueueName);
+            }
 
-                                context.Writer.Write(publicRequestTagsValue);
-                        }
-                        context.Writer.WriteObjectEnd();
-                    }
+            if(publicRequest.IsSetTags())
+            {
+                context.Writer.WritePropertyName("tags");
+                context.Writer.WriteStartObject();
+                foreach (var publicRequestTagsKvp in publicRequest.Tags)
+                {
+                    context.Writer.WritePropertyName(publicRequestTagsKvp.Key);
+                    var publicRequestTagsValue = publicRequestTagsKvp.Value;
 
-                    writer.WriteObjectEnd();
+                        context.Writer.WriteStringValue(publicRequestTagsValue);
                 }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WriteEndObject();
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueResponseUnmarshaller.cs
index aa2d7225ec0b..6d07f2f11d56 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/CreateQueueResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class CreateQueueResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             CreateQueueResponse response = new CreateQueueResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("QueueUrl", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.QueueUrl = unmarshaller.Unmarshall(context);
+                    response.QueueUrl = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,47 +72,48 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAttributeName"))
                 {
-                    return InvalidAttributeNameExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAttributeNameExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAttributeValue"))
                 {
-                    return InvalidAttributeValueExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAttributeValueExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDeletedRecently"))
                 {
-                    return QueueDeletedRecentlyExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDeletedRecentlyExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueNameExists"))
                 {
-                    return QueueNameExistsExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueNameExistsExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestEntryMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestEntryMarshaller.cs
index 9f1311ef86c7..05e4c6fcfb06 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestEntryMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestEntryMarshaller.cs
@@ -28,8 +28,6 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -51,13 +49,13 @@ public void Marshall(DeleteMessageBatchRequestEntry requestObject, JsonMarshalle
             if(requestObject.IsSetId())
             {
                 context.Writer.WritePropertyName("Id");
-                context.Writer.Write(requestObject.Id);
+                context.Writer.WriteStringValue(requestObject.Id);
             }
 
             if(requestObject.IsSetReceiptHandle())
             {
                 context.Writer.WritePropertyName("ReceiptHandle");
-                context.Writer.Write(requestObject.ReceiptHandle);
+                context.Writer.WriteStringValue(requestObject.ReceiptHandle);
             }
 
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestMarshaller.cs
index deacca51a8b3..c0ba28e79e4f 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,42 +64,47 @@ public IRequest Marshall(DeleteMessageBatchRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetEntries())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("Entries");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestEntriesListValue in publicRequest.Entries)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetEntries())
-                    {
-                        context.Writer.WritePropertyName("Entries");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestEntriesListValue in publicRequest.Entries)
-                        {
-                            context.Writer.WriteObjectStart();
-
-                            var marshaller = DeleteMessageBatchRequestEntryMarshaller.Instance;
-                            marshaller.Marshall(publicRequestEntriesListValue, context);
-
-                            context.Writer.WriteObjectEnd();
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
+                    context.Writer.WriteStartObject();
 
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
+                    var marshaller = DeleteMessageBatchRequestEntryMarshaller.Instance;
+                    marshaller.Marshall(publicRequestEntriesListValue, context);
 
-                    writer.WriteObjectEnd();
+                    context.Writer.WriteEndObject();
                 }
+                context.Writer.WriteEndArray();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResponseUnmarshaller.cs
index 8348a02b3e54..43d4aefb8799 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,21 +47,21 @@ public class DeleteMessageBatchResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             DeleteMessageBatchResponse response = new DeleteMessageBatchResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Failed", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<BatchResultErrorEntry, BatchResultErrorEntryUnmarshaller>(BatchResultErrorEntryUnmarshaller.Instance);
-                    response.Failed = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<BatchResultErrorEntry, BatchResultErrorEntryUnmarshaller>(BatchResultErrorEntryUnmarshaller.Instance);
+                    response.Failed = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Successful", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<DeleteMessageBatchResultEntry, DeleteMessageBatchResultEntryUnmarshaller>(DeleteMessageBatchResultEntryUnmarshaller.Instance);
-                    response.Successful = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<DeleteMessageBatchResultEntry, DeleteMessageBatchResultEntryUnmarshaller>(DeleteMessageBatchResultEntryUnmarshaller.Instance);
+                    response.Successful = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -78,51 +78,52 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("BatchEntryIdsNotDistinct"))
                 {
-                    return BatchEntryIdsNotDistinctExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return BatchEntryIdsNotDistinctExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("EmptyBatchRequest"))
                 {
-                    return EmptyBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return EmptyBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidBatchEntryId"))
                 {
-                    return InvalidBatchEntryIdExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidBatchEntryIdExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("TooManyEntriesInBatchRequest"))
                 {
-                    return TooManyEntriesInBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return TooManyEntriesInBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResultEntryUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResultEntryUnmarshaller.cs
index 0f2af3a76e52..e76122c3c038 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResultEntryUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageBatchResultEntryUnmarshaller.cs
@@ -29,47 +29,37 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for DeleteMessageBatchResultEntry Object
     /// </summary>  
-    public class DeleteMessageBatchResultEntryUnmarshaller : IUnmarshaller<DeleteMessageBatchResultEntry, XmlUnmarshallerContext>, IUnmarshaller<DeleteMessageBatchResultEntry, JsonUnmarshallerContext>
+    public class DeleteMessageBatchResultEntryUnmarshaller : IJsonUnmarshaller<DeleteMessageBatchResultEntry, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        DeleteMessageBatchResultEntry IUnmarshaller<DeleteMessageBatchResultEntry, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public DeleteMessageBatchResultEntry Unmarshall(JsonUnmarshallerContext context)
+        public DeleteMessageBatchResultEntry Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             DeleteMessageBatchResultEntry unmarshalledObject = new DeleteMessageBatchResultEntry();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Id", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Id = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Id = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageRequestMarshaller.cs
index cc3c22dd69d5..4ea0df86f342 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,32 +64,37 @@ public IRequest Marshall(DeleteMessageRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    if(publicRequest.IsSetReceiptHandle())
-                    {
-                        context.Writer.WritePropertyName("ReceiptHandle");
-                        context.Writer.Write(publicRequest.ReceiptHandle);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetReceiptHandle())
+            {
+                context.Writer.WritePropertyName("ReceiptHandle");
+                context.Writer.WriteStringValue(publicRequest.ReceiptHandle);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageResponseUnmarshaller.cs
index 91741167dfcd..1db9e2d9ed24 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteMessageResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             DeleteMessageResponse response = new DeleteMessageResponse();
 
-
             return response;
         }
 
@@ -61,43 +60,44 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidIdFormat"))
                 {
-                    return InvalidIdFormatExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidIdFormatExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("ReceiptHandleIsInvalid"))
                 {
-                    return ReceiptHandleIsInvalidExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return ReceiptHandleIsInvalidExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueRequestMarshaller.cs
index 9d0d6480e0c9..f31da0289566 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,26 +64,31 @@ public IRequest Marshall(DeleteQueueRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueResponseUnmarshaller.cs
index c69ab6f69883..281093df1fee 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/DeleteQueueResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             DeleteQueueResponse response = new DeleteQueueResponse();
 
-
             return response;
         }
 
@@ -61,35 +60,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/EmptyBatchRequestExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/EmptyBatchRequestExceptionUnmarshaller.cs
index 1ebcdac5e771..c5a30f74b819 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/EmptyBatchRequestExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/EmptyBatchRequestExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for EmptyBatchRequestException Object
     /// </summary>  
-    public class EmptyBatchRequestExceptionUnmarshaller : IErrorResponseUnmarshaller<EmptyBatchRequestException, JsonUnmarshallerContext>
+    public class EmptyBatchRequestExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<EmptyBatchRequestException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public EmptyBatchRequestException Unmarshall(JsonUnmarshallerContext context)
+        public EmptyBatchRequestException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public EmptyBatchRequestException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public EmptyBatchRequestException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public EmptyBatchRequestException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public EmptyBatchRequestException Unmarshall(JsonUnmarshallerContext context, Am
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesRequestMarshaller.cs
index 1ffb99f7342b..63872f6bdd7c 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,37 +64,42 @@ public IRequest Marshall(GetQueueAttributesRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetAttributeNames())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("AttributeNames");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestAttributeNamesListValue in publicRequest.AttributeNames)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetAttributeNames())
-                    {
-                        context.Writer.WritePropertyName("AttributeNames");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestAttributeNamesListValue in publicRequest.AttributeNames)
-                        {
-                                context.Writer.Write(publicRequestAttributeNamesListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    writer.WriteObjectEnd();
+                        context.Writer.WriteStringValue(publicRequestAttributeNamesListValue);
                 }
+                context.Writer.WriteEndArray();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesResponseUnmarshaller.cs
index 95ce3c798e46..21966364db6b 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueAttributesResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class GetQueueAttributesResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             GetQueueAttributesResponse response = new GetQueueAttributesResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Attributes", targetDepth))
                 {
-                    var unmarshaller = new DictionaryUnmarshaller<string, string, StringUnmarshaller, StringUnmarshaller>(StringUnmarshaller.Instance, StringUnmarshaller.Instance);
-                    response.Attributes = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonDictionaryUnmarshaller<string, string, StringUnmarshaller, StringUnmarshaller>(StringUnmarshaller.Instance, StringUnmarshaller.Instance);
+                    response.Attributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,39 +72,40 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAttributeName"))
                 {
-                    return InvalidAttributeNameExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAttributeNameExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlRequestMarshaller.cs
index 85d5ee25107e..222e020c3ec4 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,32 +64,37 @@ public IRequest Marshall(GetQueueUrlRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueName())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueName())
-                    {
-                        context.Writer.WritePropertyName("QueueName");
-                        context.Writer.Write(publicRequest.QueueName);
-                    }
-
-                    if(publicRequest.IsSetQueueOwnerAWSAccountId())
-                    {
-                        context.Writer.WritePropertyName("QueueOwnerAWSAccountId");
-                        context.Writer.Write(publicRequest.QueueOwnerAWSAccountId);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
+                context.Writer.WritePropertyName("QueueName");
+                context.Writer.WriteStringValue(publicRequest.QueueName);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueOwnerAWSAccountId())
+            {
+                context.Writer.WritePropertyName("QueueOwnerAWSAccountId");
+                context.Writer.WriteStringValue(publicRequest.QueueOwnerAWSAccountId);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlResponseUnmarshaller.cs
index a6570571cdcb..089f64c5a95c 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/GetQueueUrlResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class GetQueueUrlResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             GetQueueUrlResponse response = new GetQueueUrlResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("QueueUrl", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.QueueUrl = unmarshaller.Unmarshall(context);
+                    response.QueueUrl = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,35 +72,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAddressExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAddressExceptionUnmarshaller.cs
index c643c83a34d4..032fadb6542a 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAddressExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAddressExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidAddressException Object
     /// </summary>  
-    public class InvalidAddressExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidAddressException, JsonUnmarshallerContext>
+    public class InvalidAddressExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidAddressException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidAddressException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidAddressException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidAddressException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidAddressException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidAddressException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidAddressException Unmarshall(JsonUnmarshallerContext context, Amazo
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeNameExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeNameExceptionUnmarshaller.cs
index 8a70e796e1f9..3560b9d2a9ce 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeNameExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeNameExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidAttributeNameException Object
     /// </summary>  
-    public class InvalidAttributeNameExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidAttributeNameException, JsonUnmarshallerContext>
+    public class InvalidAttributeNameExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidAttributeNameException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidAttributeNameException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidAttributeNameException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidAttributeNameException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidAttributeNameException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidAttributeNameException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidAttributeNameException Unmarshall(JsonUnmarshallerContext context,
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeValueExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeValueExceptionUnmarshaller.cs
index 361999d1e68e..c40057b3c9eb 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeValueExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidAttributeValueExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidAttributeValueException Object
     /// </summary>  
-    public class InvalidAttributeValueExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidAttributeValueException, JsonUnmarshallerContext>
+    public class InvalidAttributeValueExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidAttributeValueException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidAttributeValueException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidAttributeValueException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidAttributeValueException Unmarshall(JsonUnmarshallerContext context
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidAttributeValueException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidAttributeValueException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidAttributeValueException Unmarshall(JsonUnmarshallerContext context
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidBatchEntryIdExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidBatchEntryIdExceptionUnmarshaller.cs
index 5a86b03c32e5..f8a75d0ddd31 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidBatchEntryIdExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidBatchEntryIdExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidBatchEntryIdException Object
     /// </summary>  
-    public class InvalidBatchEntryIdExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidBatchEntryIdException, JsonUnmarshallerContext>
+    public class InvalidBatchEntryIdExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidBatchEntryIdException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidBatchEntryIdException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidBatchEntryIdException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidBatchEntryIdException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidBatchEntryIdException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidBatchEntryIdException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidBatchEntryIdException Unmarshall(JsonUnmarshallerContext context,
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidIdFormatExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidIdFormatExceptionUnmarshaller.cs
index e52cf848f712..7c5694809872 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidIdFormatExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidIdFormatExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidIdFormatException Object
     /// </summary>  
-    public class InvalidIdFormatExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidIdFormatException, JsonUnmarshallerContext>
+    public class InvalidIdFormatExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidIdFormatException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidIdFormatException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidIdFormatException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidIdFormatException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidIdFormatException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidIdFormatException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidIdFormatException Unmarshall(JsonUnmarshallerContext context, Amaz
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidMessageContentsExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidMessageContentsExceptionUnmarshaller.cs
index 9d06dac5719e..4caf0b736caa 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidMessageContentsExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidMessageContentsExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidMessageContentsException Object
     /// </summary>  
-    public class InvalidMessageContentsExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidMessageContentsException, JsonUnmarshallerContext>
+    public class InvalidMessageContentsExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidMessageContentsException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidMessageContentsException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidMessageContentsException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidMessageContentsException Unmarshall(JsonUnmarshallerContext contex
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidMessageContentsException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidMessageContentsException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidMessageContentsException Unmarshall(JsonUnmarshallerContext contex
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidSecurityExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidSecurityExceptionUnmarshaller.cs
index ce7d598ce5cb..37f0e7afefe7 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidSecurityExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/InvalidSecurityExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for InvalidSecurityException Object
     /// </summary>  
-    public class InvalidSecurityExceptionUnmarshaller : IErrorResponseUnmarshaller<InvalidSecurityException, JsonUnmarshallerContext>
+    public class InvalidSecurityExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<InvalidSecurityException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidSecurityException Unmarshall(JsonUnmarshallerContext context)
+        public InvalidSecurityException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public InvalidSecurityException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public InvalidSecurityException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public InvalidSecurityException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public InvalidSecurityException Unmarshall(JsonUnmarshallerContext context, Amaz
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsAccessDeniedExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsAccessDeniedExceptionUnmarshaller.cs
index 3c9ebef153b2..a6bb742d95e6 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsAccessDeniedExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsAccessDeniedExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsAccessDeniedException Object
     /// </summary>  
-    public class KmsAccessDeniedExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsAccessDeniedException, JsonUnmarshallerContext>
+    public class KmsAccessDeniedExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsAccessDeniedException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsAccessDeniedException Unmarshall(JsonUnmarshallerContext context)
+        public KmsAccessDeniedException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsAccessDeniedException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsAccessDeniedException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsAccessDeniedException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsAccessDeniedException Unmarshall(JsonUnmarshallerContext context, Amaz
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsDisabledExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsDisabledExceptionUnmarshaller.cs
index d1da584c32fb..b84562a443bc 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsDisabledExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsDisabledExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsDisabledException Object
     /// </summary>  
-    public class KmsDisabledExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsDisabledException, JsonUnmarshallerContext>
+    public class KmsDisabledExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsDisabledException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsDisabledException Unmarshall(JsonUnmarshallerContext context)
+        public KmsDisabledException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsDisabledException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsDisabledException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsDisabledException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsDisabledException Unmarshall(JsonUnmarshallerContext context, Amazon.R
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidKeyUsageExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidKeyUsageExceptionUnmarshaller.cs
index 3921ae476e8a..db6a79f8b09f 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidKeyUsageExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidKeyUsageExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsInvalidKeyUsageException Object
     /// </summary>  
-    public class KmsInvalidKeyUsageExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsInvalidKeyUsageException, JsonUnmarshallerContext>
+    public class KmsInvalidKeyUsageExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsInvalidKeyUsageException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsInvalidKeyUsageException Unmarshall(JsonUnmarshallerContext context)
+        public KmsInvalidKeyUsageException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsInvalidKeyUsageException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsInvalidKeyUsageException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsInvalidKeyUsageException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsInvalidKeyUsageException Unmarshall(JsonUnmarshallerContext context, A
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidStateExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidStateExceptionUnmarshaller.cs
index ad892962535f..aa25bb41bb7a 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidStateExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsInvalidStateExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsInvalidStateException Object
     /// </summary>  
-    public class KmsInvalidStateExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsInvalidStateException, JsonUnmarshallerContext>
+    public class KmsInvalidStateExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsInvalidStateException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsInvalidStateException Unmarshall(JsonUnmarshallerContext context)
+        public KmsInvalidStateException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsInvalidStateException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsInvalidStateException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsInvalidStateException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsInvalidStateException Unmarshall(JsonUnmarshallerContext context, Amaz
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsNotFoundExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsNotFoundExceptionUnmarshaller.cs
index 18a5eb421cfa..d070f34a5550 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsNotFoundExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsNotFoundExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsNotFoundException Object
     /// </summary>  
-    public class KmsNotFoundExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsNotFoundException, JsonUnmarshallerContext>
+    public class KmsNotFoundExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsNotFoundException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsNotFoundException Unmarshall(JsonUnmarshallerContext context)
+        public KmsNotFoundException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsNotFoundException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsNotFoundException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsNotFoundException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsNotFoundException Unmarshall(JsonUnmarshallerContext context, Amazon.R
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsOptInRequiredExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsOptInRequiredExceptionUnmarshaller.cs
index 7bbe2870f832..fdd36d98c083 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsOptInRequiredExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsOptInRequiredExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsOptInRequiredException Object
     /// </summary>  
-    public class KmsOptInRequiredExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsOptInRequiredException, JsonUnmarshallerContext>
+    public class KmsOptInRequiredExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsOptInRequiredException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsOptInRequiredException Unmarshall(JsonUnmarshallerContext context)
+        public KmsOptInRequiredException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsOptInRequiredException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsOptInRequiredException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsOptInRequiredException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsOptInRequiredException Unmarshall(JsonUnmarshallerContext context, Ama
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsThrottledExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsThrottledExceptionUnmarshaller.cs
index ede516629f1d..1c1da921bc8f 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsThrottledExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/KmsThrottledExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for KmsThrottledException Object
     /// </summary>  
-    public class KmsThrottledExceptionUnmarshaller : IErrorResponseUnmarshaller<KmsThrottledException, JsonUnmarshallerContext>
+    public class KmsThrottledExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<KmsThrottledException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsThrottledException Unmarshall(JsonUnmarshallerContext context)
+        public KmsThrottledException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public KmsThrottledException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public KmsThrottledException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public KmsThrottledException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public KmsThrottledException Unmarshall(JsonUnmarshallerContext context, Amazon.
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesRequestMarshaller.cs
index 0322d7ef235a..0abf445c7f66 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,38 +64,43 @@ public IRequest Marshall(ListDeadLetterSourceQueuesRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetMaxResults())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetMaxResults())
-                    {
-                        context.Writer.WritePropertyName("MaxResults");
-                        context.Writer.Write(publicRequest.MaxResults.Value);
-                    }
-
-                    if(publicRequest.IsSetNextToken())
-                    {
-                        context.Writer.WritePropertyName("NextToken");
-                        context.Writer.Write(publicRequest.NextToken);
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
+                context.Writer.WritePropertyName("MaxResults");
+                context.Writer.WriteNumberValue(publicRequest.MaxResults.Value);
+            }
 
-                    writer.WriteObjectEnd();
-                }
+            if(publicRequest.IsSetNextToken())
+            {
+                context.Writer.WritePropertyName("NextToken");
+                context.Writer.WriteStringValue(publicRequest.NextToken);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesResponseUnmarshaller.cs
index 70c23b749112..d6b2361be0dc 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListDeadLetterSourceQueuesResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,21 +47,21 @@ public class ListDeadLetterSourceQueuesResponseUnmarshaller : JsonResponseUnmars
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             ListDeadLetterSourceQueuesResponse response = new ListDeadLetterSourceQueuesResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("NextToken", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.NextToken = unmarshaller.Unmarshall(context);
+                    response.NextToken = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("queueUrls", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<string, StringUnmarshaller>(StringUnmarshaller.Instance);
-                    response.QueueUrls = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<string, StringUnmarshaller>(StringUnmarshaller.Instance);
+                    response.QueueUrls = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -78,35 +78,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksRequestMarshaller.cs
index f40eeda9d9c8..7b0c741fb1ad 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,32 +64,37 @@ public IRequest Marshall(ListMessageMoveTasksRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetMaxResults())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetMaxResults())
-                    {
-                        context.Writer.WritePropertyName("MaxResults");
-                        context.Writer.Write(publicRequest.MaxResults.Value);
-                    }
-
-                    if(publicRequest.IsSetSourceArn())
-                    {
-                        context.Writer.WritePropertyName("SourceArn");
-                        context.Writer.Write(publicRequest.SourceArn);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
+                context.Writer.WritePropertyName("MaxResults");
+                context.Writer.WriteNumberValue(publicRequest.MaxResults.Value);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetSourceArn())
+            {
+                context.Writer.WritePropertyName("SourceArn");
+                context.Writer.WriteStringValue(publicRequest.SourceArn);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResponseUnmarshaller.cs
index 645cb79da5b1..a165d819f2ab 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class ListMessageMoveTasksResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             ListMessageMoveTasksResponse response = new ListMessageMoveTasksResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Results", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<ListMessageMoveTasksResultEntry, ListMessageMoveTasksResultEntryUnmarshaller>(ListMessageMoveTasksResultEntryUnmarshaller.Instance);
-                    response.Results = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<ListMessageMoveTasksResultEntry, ListMessageMoveTasksResultEntryUnmarshaller>(ListMessageMoveTasksResultEntryUnmarshaller.Instance);
+                    response.Results = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,35 +72,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("ResourceNotFoundException"))
                 {
-                    return ResourceNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return ResourceNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResultEntryUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResultEntryUnmarshaller.cs
index 9500d0e15064..302846545c44 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResultEntryUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListMessageMoveTasksResultEntryUnmarshaller.cs
@@ -29,95 +29,85 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for ListMessageMoveTasksResultEntry Object
     /// </summary>  
-    public class ListMessageMoveTasksResultEntryUnmarshaller : IUnmarshaller<ListMessageMoveTasksResultEntry, XmlUnmarshallerContext>, IUnmarshaller<ListMessageMoveTasksResultEntry, JsonUnmarshallerContext>
+    public class ListMessageMoveTasksResultEntryUnmarshaller : IJsonUnmarshaller<ListMessageMoveTasksResultEntry, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        ListMessageMoveTasksResultEntry IUnmarshaller<ListMessageMoveTasksResultEntry, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public ListMessageMoveTasksResultEntry Unmarshall(JsonUnmarshallerContext context)
+        public ListMessageMoveTasksResultEntry Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             ListMessageMoveTasksResultEntry unmarshalledObject = new ListMessageMoveTasksResultEntry();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("ApproximateNumberOfMessagesMoved", targetDepth))
                 {
                     var unmarshaller = NullableLongUnmarshaller.Instance;
-                    unmarshalledObject.ApproximateNumberOfMessagesMoved = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.ApproximateNumberOfMessagesMoved = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("ApproximateNumberOfMessagesToMove", targetDepth))
                 {
                     var unmarshaller = NullableLongUnmarshaller.Instance;
-                    unmarshalledObject.ApproximateNumberOfMessagesToMove = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.ApproximateNumberOfMessagesToMove = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("DestinationArn", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.DestinationArn = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.DestinationArn = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("FailureReason", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.FailureReason = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.FailureReason = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MaxNumberOfMessagesPerSecond", targetDepth))
                 {
                     var unmarshaller = NullableIntUnmarshaller.Instance;
-                    unmarshalledObject.MaxNumberOfMessagesPerSecond = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MaxNumberOfMessagesPerSecond = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("SourceArn", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.SourceArn = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.SourceArn = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("StartedTimestamp", targetDepth))
                 {
                     var unmarshaller = NullableLongUnmarshaller.Instance;
-                    unmarshalledObject.StartedTimestamp = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.StartedTimestamp = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Status", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Status = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Status = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("TaskHandle", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.TaskHandle = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.TaskHandle = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsRequestMarshaller.cs
index d2d8b8a966ce..bc9231d81964 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,26 +64,31 @@ public IRequest Marshall(ListQueueTagsRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsResponseUnmarshaller.cs
index ce70e6a20671..3c8141b245ad 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueueTagsResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class ListQueueTagsResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             ListQueueTagsResponse response = new ListQueueTagsResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Tags", targetDepth))
                 {
-                    var unmarshaller = new DictionaryUnmarshaller<string, string, StringUnmarshaller, StringUnmarshaller>(StringUnmarshaller.Instance, StringUnmarshaller.Instance);
-                    response.Tags = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonDictionaryUnmarshaller<string, string, StringUnmarshaller, StringUnmarshaller>(StringUnmarshaller.Instance, StringUnmarshaller.Instance);
+                    response.Tags = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,35 +72,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesRequestMarshaller.cs
index d116f4d48496..b9eee0176d16 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,38 +64,43 @@ public IRequest Marshall(ListQueuesRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetMaxResults())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetMaxResults())
-                    {
-                        context.Writer.WritePropertyName("MaxResults");
-                        context.Writer.Write(publicRequest.MaxResults.Value);
-                    }
-
-                    if(publicRequest.IsSetNextToken())
-                    {
-                        context.Writer.WritePropertyName("NextToken");
-                        context.Writer.Write(publicRequest.NextToken);
-                    }
-
-                    if(publicRequest.IsSetQueueNamePrefix())
-                    {
-                        context.Writer.WritePropertyName("QueueNamePrefix");
-                        context.Writer.Write(publicRequest.QueueNamePrefix);
-                    }
+                context.Writer.WritePropertyName("MaxResults");
+                context.Writer.WriteNumberValue(publicRequest.MaxResults.Value);
+            }
 
-                    writer.WriteObjectEnd();
-                }
+            if(publicRequest.IsSetNextToken())
+            {
+                context.Writer.WritePropertyName("NextToken");
+                context.Writer.WriteStringValue(publicRequest.NextToken);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueNamePrefix())
+            {
+                context.Writer.WritePropertyName("QueueNamePrefix");
+                context.Writer.WriteStringValue(publicRequest.QueueNamePrefix);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesResponseUnmarshaller.cs
index efc62b1ee04b..2fff97ffc4e1 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ListQueuesResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,21 +47,21 @@ public class ListQueuesResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             ListQueuesResponse response = new ListQueuesResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("NextToken", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.NextToken = unmarshaller.Unmarshall(context);
+                    response.NextToken = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("QueueUrls", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<string, StringUnmarshaller>(StringUnmarshaller.Instance);
-                    response.QueueUrls = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<string, StringUnmarshaller>(StringUnmarshaller.Instance);
+                    response.QueueUrls = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -78,31 +78,32 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueMarshaller.cs
index 940423c03b24..2e6cd103a8d1 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueMarshaller.cs
@@ -28,8 +28,6 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -51,41 +49,41 @@ public void Marshall(MessageAttributeValue requestObject, JsonMarshallerContext
             if(requestObject.IsSetBinaryListValues())
             {
                 context.Writer.WritePropertyName("BinaryListValues");
-                context.Writer.WriteArrayStart();
+                context.Writer.WriteStartArray();
                 foreach(var requestObjectBinaryListValuesListValue in requestObject.BinaryListValues)
                 {
-                    context.Writer.Write(StringUtils.FromMemoryStream(requestObjectBinaryListValuesListValue));
+                    context.Writer.WriteStringValue(StringUtils.FromMemoryStream(requestObjectBinaryListValuesListValue));
                 }
-                context.Writer.WriteArrayEnd();
+                context.Writer.WriteEndArray();
             }
 
             if(requestObject.IsSetBinaryValue())
             {
                 context.Writer.WritePropertyName("BinaryValue");
-                context.Writer.Write(StringUtils.FromMemoryStream(requestObject.BinaryValue));
+                context.Writer.WriteStringValue(StringUtils.FromMemoryStream(requestObject.BinaryValue));
             }
 
             if(requestObject.IsSetDataType())
             {
                 context.Writer.WritePropertyName("DataType");
-                context.Writer.Write(requestObject.DataType);
+                context.Writer.WriteStringValue(requestObject.DataType);
             }
 
             if(requestObject.IsSetStringListValues())
             {
                 context.Writer.WritePropertyName("StringListValues");
-                context.Writer.WriteArrayStart();
+                context.Writer.WriteStartArray();
                 foreach(var requestObjectStringListValuesListValue in requestObject.StringListValues)
                 {
-                        context.Writer.Write(requestObjectStringListValuesListValue);
+                        context.Writer.WriteStringValue(requestObjectStringListValuesListValue);
                 }
-                context.Writer.WriteArrayEnd();
+                context.Writer.WriteEndArray();
             }
 
             if(requestObject.IsSetStringValue())
             {
                 context.Writer.WritePropertyName("StringValue");
-                context.Writer.Write(requestObject.StringValue);
+                context.Writer.WriteStringValue(requestObject.StringValue);
             }
 
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueUnmarshaller.cs
index 33bb8a435d6b..9a456d550f31 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageAttributeValueUnmarshaller.cs
@@ -29,71 +29,61 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for MessageAttributeValue Object
     /// </summary>  
-    public class MessageAttributeValueUnmarshaller : IUnmarshaller<MessageAttributeValue, XmlUnmarshallerContext>, IUnmarshaller<MessageAttributeValue, JsonUnmarshallerContext>
+    public class MessageAttributeValueUnmarshaller : IJsonUnmarshaller<MessageAttributeValue, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        MessageAttributeValue IUnmarshaller<MessageAttributeValue, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public MessageAttributeValue Unmarshall(JsonUnmarshallerContext context)
+        public MessageAttributeValue Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             MessageAttributeValue unmarshalledObject = new MessageAttributeValue();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("BinaryListValues", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<MemoryStream, MemoryStreamUnmarshaller>(MemoryStreamUnmarshaller.Instance);
-                    unmarshalledObject.BinaryListValues = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<MemoryStream, MemoryStreamUnmarshaller>(MemoryStreamUnmarshaller.Instance);
+                    unmarshalledObject.BinaryListValues = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("BinaryValue", targetDepth))
                 {
                     var unmarshaller = MemoryStreamUnmarshaller.Instance;
-                    unmarshalledObject.BinaryValue = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.BinaryValue = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("DataType", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.DataType = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.DataType = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("StringListValues", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<string, StringUnmarshaller>(StringUnmarshaller.Instance);
-                    unmarshalledObject.StringListValues = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<string, StringUnmarshaller>(StringUnmarshaller.Instance);
+                    unmarshalledObject.StringListValues = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("StringValue", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.StringValue = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.StringValue = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageNotInflightExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageNotInflightExceptionUnmarshaller.cs
index 4a92a4ddd638..59510b33e918 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageNotInflightExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageNotInflightExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for MessageNotInflightException Object
     /// </summary>  
-    public class MessageNotInflightExceptionUnmarshaller : IErrorResponseUnmarshaller<MessageNotInflightException, JsonUnmarshallerContext>
+    public class MessageNotInflightExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<MessageNotInflightException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public MessageNotInflightException Unmarshall(JsonUnmarshallerContext context)
+        public MessageNotInflightException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public MessageNotInflightException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public MessageNotInflightException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public MessageNotInflightException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public MessageNotInflightException Unmarshall(JsonUnmarshallerContext context, A
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageSystemAttributeValueMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageSystemAttributeValueMarshaller.cs
index 9b24b0aa2767..c90aa7361e4e 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageSystemAttributeValueMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageSystemAttributeValueMarshaller.cs
@@ -28,8 +28,6 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -51,41 +49,41 @@ public void Marshall(MessageSystemAttributeValue requestObject, JsonMarshallerCo
             if(requestObject.IsSetBinaryListValues())
             {
                 context.Writer.WritePropertyName("BinaryListValues");
-                context.Writer.WriteArrayStart();
+                context.Writer.WriteStartArray();
                 foreach(var requestObjectBinaryListValuesListValue in requestObject.BinaryListValues)
                 {
-                    context.Writer.Write(StringUtils.FromMemoryStream(requestObjectBinaryListValuesListValue));
+                    context.Writer.WriteStringValue(StringUtils.FromMemoryStream(requestObjectBinaryListValuesListValue));
                 }
-                context.Writer.WriteArrayEnd();
+                context.Writer.WriteEndArray();
             }
 
             if(requestObject.IsSetBinaryValue())
             {
                 context.Writer.WritePropertyName("BinaryValue");
-                context.Writer.Write(StringUtils.FromMemoryStream(requestObject.BinaryValue));
+                context.Writer.WriteStringValue(StringUtils.FromMemoryStream(requestObject.BinaryValue));
             }
 
             if(requestObject.IsSetDataType())
             {
                 context.Writer.WritePropertyName("DataType");
-                context.Writer.Write(requestObject.DataType);
+                context.Writer.WriteStringValue(requestObject.DataType);
             }
 
             if(requestObject.IsSetStringListValues())
             {
                 context.Writer.WritePropertyName("StringListValues");
-                context.Writer.WriteArrayStart();
+                context.Writer.WriteStartArray();
                 foreach(var requestObjectStringListValuesListValue in requestObject.StringListValues)
                 {
-                        context.Writer.Write(requestObjectStringListValuesListValue);
+                        context.Writer.WriteStringValue(requestObjectStringListValuesListValue);
                 }
-                context.Writer.WriteArrayEnd();
+                context.Writer.WriteEndArray();
             }
 
             if(requestObject.IsSetStringValue())
             {
                 context.Writer.WritePropertyName("StringValue");
-                context.Writer.Write(requestObject.StringValue);
+                context.Writer.WriteStringValue(requestObject.StringValue);
             }
 
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageUnmarshaller.cs
index 2b1654deab3b..d1294987fe3e 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/MessageUnmarshaller.cs
@@ -29,83 +29,73 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for Message Object
     /// </summary>  
-    public class MessageUnmarshaller : IUnmarshaller<Message, XmlUnmarshallerContext>, IUnmarshaller<Message, JsonUnmarshallerContext>
+    public class MessageUnmarshaller : IJsonUnmarshaller<Message, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        Message IUnmarshaller<Message, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public Message Unmarshall(JsonUnmarshallerContext context)
+        public Message Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             Message unmarshalledObject = new Message();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Attributes", targetDepth))
                 {
-                    var unmarshaller = new DictionaryUnmarshaller<string, string, StringUnmarshaller, StringUnmarshaller>(StringUnmarshaller.Instance, StringUnmarshaller.Instance);
-                    unmarshalledObject.Attributes = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonDictionaryUnmarshaller<string, string, StringUnmarshaller, StringUnmarshaller>(StringUnmarshaller.Instance, StringUnmarshaller.Instance);
+                    unmarshalledObject.Attributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Body", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Body = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Body = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfBody", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MD5OfBody = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MD5OfBody = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfMessageAttributes", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MD5OfMessageAttributes = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MD5OfMessageAttributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MessageAttributes", targetDepth))
                 {
-                    var unmarshaller = new DictionaryUnmarshaller<string, MessageAttributeValue, StringUnmarshaller, MessageAttributeValueUnmarshaller>(StringUnmarshaller.Instance, MessageAttributeValueUnmarshaller.Instance);
-                    unmarshalledObject.MessageAttributes = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonDictionaryUnmarshaller<string, MessageAttributeValue, StringUnmarshaller, MessageAttributeValueUnmarshaller>(StringUnmarshaller.Instance, MessageAttributeValueUnmarshaller.Instance);
+                    unmarshalledObject.MessageAttributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MessageId", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MessageId = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MessageId = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("ReceiptHandle", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.ReceiptHandle = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.ReceiptHandle = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/OverLimitExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/OverLimitExceptionUnmarshaller.cs
index cd436b109ed3..c7eb8ab0014e 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/OverLimitExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/OverLimitExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for OverLimitException Object
     /// </summary>  
-    public class OverLimitExceptionUnmarshaller : IErrorResponseUnmarshaller<OverLimitException, JsonUnmarshallerContext>
+    public class OverLimitExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<OverLimitException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public OverLimitException Unmarshall(JsonUnmarshallerContext context)
+        public OverLimitException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public OverLimitException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public OverLimitException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public OverLimitException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public OverLimitException Unmarshall(JsonUnmarshallerContext context, Amazon.Run
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueInProgressExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueInProgressExceptionUnmarshaller.cs
index 3b31336060a9..68b13a2b0ef0 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueInProgressExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueInProgressExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for PurgeQueueInProgressException Object
     /// </summary>  
-    public class PurgeQueueInProgressExceptionUnmarshaller : IErrorResponseUnmarshaller<PurgeQueueInProgressException, JsonUnmarshallerContext>
+    public class PurgeQueueInProgressExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<PurgeQueueInProgressException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public PurgeQueueInProgressException Unmarshall(JsonUnmarshallerContext context)
+        public PurgeQueueInProgressException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public PurgeQueueInProgressException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public PurgeQueueInProgressException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public PurgeQueueInProgressException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public PurgeQueueInProgressException Unmarshall(JsonUnmarshallerContext context,
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueRequestMarshaller.cs
index 3a7d81c07fc5..9c388ca0bbaa 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,26 +64,31 @@ public IRequest Marshall(PurgeQueueRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueResponseUnmarshaller.cs
index 6e8e282ca9ad..829acf66ebab 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/PurgeQueueResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             PurgeQueueResponse response = new PurgeQueueResponse();
 
-
             return response;
         }
 
@@ -61,39 +60,40 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("PurgeQueueInProgress"))
                 {
-                    return PurgeQueueInProgressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return PurgeQueueInProgressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDeletedRecentlyExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDeletedRecentlyExceptionUnmarshaller.cs
index c700acfc8974..1919f77b0f4b 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDeletedRecentlyExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDeletedRecentlyExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for QueueDeletedRecentlyException Object
     /// </summary>  
-    public class QueueDeletedRecentlyExceptionUnmarshaller : IErrorResponseUnmarshaller<QueueDeletedRecentlyException, JsonUnmarshallerContext>
+    public class QueueDeletedRecentlyExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<QueueDeletedRecentlyException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public QueueDeletedRecentlyException Unmarshall(JsonUnmarshallerContext context)
+        public QueueDeletedRecentlyException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public QueueDeletedRecentlyException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public QueueDeletedRecentlyException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public QueueDeletedRecentlyException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public QueueDeletedRecentlyException Unmarshall(JsonUnmarshallerContext context,
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDoesNotExistExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDoesNotExistExceptionUnmarshaller.cs
index b0c3e7b763dd..ff230eac2f53 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDoesNotExistExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueDoesNotExistExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for QueueDoesNotExistException Object
     /// </summary>  
-    public class QueueDoesNotExistExceptionUnmarshaller : IErrorResponseUnmarshaller<QueueDoesNotExistException, JsonUnmarshallerContext>
+    public class QueueDoesNotExistExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<QueueDoesNotExistException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public QueueDoesNotExistException Unmarshall(JsonUnmarshallerContext context)
+        public QueueDoesNotExistException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public QueueDoesNotExistException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public QueueDoesNotExistException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public QueueDoesNotExistException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public QueueDoesNotExistException Unmarshall(JsonUnmarshallerContext context, Am
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueNameExistsExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueNameExistsExceptionUnmarshaller.cs
index 73496be2b31c..05462ef52d00 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueNameExistsExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/QueueNameExistsExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for QueueNameExistsException Object
     /// </summary>  
-    public class QueueNameExistsExceptionUnmarshaller : IErrorResponseUnmarshaller<QueueNameExistsException, JsonUnmarshallerContext>
+    public class QueueNameExistsExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<QueueNameExistsException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public QueueNameExistsException Unmarshall(JsonUnmarshallerContext context)
+        public QueueNameExistsException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public QueueNameExistsException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public QueueNameExistsException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public QueueNameExistsException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public QueueNameExistsException Unmarshall(JsonUnmarshallerContext context, Amaz
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiptHandleIsInvalidExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiptHandleIsInvalidExceptionUnmarshaller.cs
index 6a03c2e54a8e..93dff990f677 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiptHandleIsInvalidExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiptHandleIsInvalidExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for ReceiptHandleIsInvalidException Object
     /// </summary>  
-    public class ReceiptHandleIsInvalidExceptionUnmarshaller : IErrorResponseUnmarshaller<ReceiptHandleIsInvalidException, JsonUnmarshallerContext>
+    public class ReceiptHandleIsInvalidExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<ReceiptHandleIsInvalidException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public ReceiptHandleIsInvalidException Unmarshall(JsonUnmarshallerContext context)
+        public ReceiptHandleIsInvalidException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public ReceiptHandleIsInvalidException Unmarshall(JsonUnmarshallerContext contex
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public ReceiptHandleIsInvalidException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public ReceiptHandleIsInvalidException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public ReceiptHandleIsInvalidException Unmarshall(JsonUnmarshallerContext contex
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageRequestMarshaller.cs
index 7f53087690e9..dbc9926664f7 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,83 +64,88 @@ public IRequest Marshall(ReceiveMessageRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetAttributeNames())
+            {
+                context.Writer.WritePropertyName("AttributeNames");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestAttributeNamesListValue in publicRequest.AttributeNames)
+                {
+                        context.Writer.WriteStringValue(publicRequestAttributeNamesListValue);
+                }
+                context.Writer.WriteEndArray();
+            }
+
+            if(publicRequest.IsSetMaxNumberOfMessages())
+            {
+                context.Writer.WritePropertyName("MaxNumberOfMessages");
+                context.Writer.WriteNumberValue(publicRequest.MaxNumberOfMessages.Value);
+            }
+
+            if(publicRequest.IsSetMessageAttributeNames())
+            {
+                context.Writer.WritePropertyName("MessageAttributeNames");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestMessageAttributeNamesListValue in publicRequest.MessageAttributeNames)
+                {
+                        context.Writer.WriteStringValue(publicRequestMessageAttributeNamesListValue);
+                }
+                context.Writer.WriteEndArray();
+            }
+
+            if(publicRequest.IsSetMessageSystemAttributeNames())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("MessageSystemAttributeNames");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestMessageSystemAttributeNamesListValue in publicRequest.MessageSystemAttributeNames)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetAttributeNames())
-                    {
-                        context.Writer.WritePropertyName("AttributeNames");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestAttributeNamesListValue in publicRequest.AttributeNames)
-                        {
-                                context.Writer.Write(publicRequestAttributeNamesListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
-
-                    if(publicRequest.IsSetMaxNumberOfMessages())
-                    {
-                        context.Writer.WritePropertyName("MaxNumberOfMessages");
-                        context.Writer.Write(publicRequest.MaxNumberOfMessages.Value);
-                    }
-
-                    if(publicRequest.IsSetMessageAttributeNames())
-                    {
-                        context.Writer.WritePropertyName("MessageAttributeNames");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestMessageAttributeNamesListValue in publicRequest.MessageAttributeNames)
-                        {
-                                context.Writer.Write(publicRequestMessageAttributeNamesListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
-
-                    if(publicRequest.IsSetMessageSystemAttributeNames())
-                    {
-                        context.Writer.WritePropertyName("MessageSystemAttributeNames");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestMessageSystemAttributeNamesListValue in publicRequest.MessageSystemAttributeNames)
-                        {
-                                context.Writer.Write(publicRequestMessageSystemAttributeNamesListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    if(publicRequest.IsSetReceiveRequestAttemptId())
-                    {
-                        context.Writer.WritePropertyName("ReceiveRequestAttemptId");
-                        context.Writer.Write(publicRequest.ReceiveRequestAttemptId);
-                    }
-
-                    if(publicRequest.IsSetVisibilityTimeout())
-                    {
-                        context.Writer.WritePropertyName("VisibilityTimeout");
-                        context.Writer.Write(publicRequest.VisibilityTimeout.Value);
-                    }
-
-                    if(publicRequest.IsSetWaitTimeSeconds())
-                    {
-                        context.Writer.WritePropertyName("WaitTimeSeconds");
-                        context.Writer.Write(publicRequest.WaitTimeSeconds.Value);
-                    }
-
-                    writer.WriteObjectEnd();
+                        context.Writer.WriteStringValue(publicRequestMessageSystemAttributeNamesListValue);
                 }
+                context.Writer.WriteEndArray();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            if(publicRequest.IsSetReceiveRequestAttemptId())
+            {
+                context.Writer.WritePropertyName("ReceiveRequestAttemptId");
+                context.Writer.WriteStringValue(publicRequest.ReceiveRequestAttemptId);
+            }
+
+            if(publicRequest.IsSetVisibilityTimeout())
+            {
+                context.Writer.WritePropertyName("VisibilityTimeout");
+                context.Writer.WriteNumberValue(publicRequest.VisibilityTimeout.Value);
+            }
+
+            if(publicRequest.IsSetWaitTimeSeconds())
+            {
+                context.Writer.WritePropertyName("WaitTimeSeconds");
+                context.Writer.WriteNumberValue(publicRequest.WaitTimeSeconds.Value);
+            }
+
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageResponseUnmarshaller.cs
index 28c29a16eea6..752f9371f62d 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ReceiveMessageResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class ReceiveMessageResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             ReceiveMessageResponse response = new ReceiveMessageResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Messages", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<Message, MessageUnmarshaller>(MessageUnmarshaller.Instance);
-                    response.Messages = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<Message, MessageUnmarshaller>(MessageUnmarshaller.Instance);
+                    response.Messages = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,67 +72,68 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsAccessDenied"))
                 {
-                    return KmsAccessDeniedExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsAccessDeniedExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsDisabled"))
                 {
-                    return KmsDisabledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsDisabledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsInvalidKeyUsage"))
                 {
-                    return KmsInvalidKeyUsageExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsInvalidKeyUsageExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsInvalidState"))
                 {
-                    return KmsInvalidStateExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsInvalidStateExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsNotFound"))
                 {
-                    return KmsNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsOptInRequired"))
                 {
-                    return KmsOptInRequiredExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsOptInRequiredExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsThrottled"))
                 {
-                    return KmsThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("OverLimit"))
                 {
-                    return OverLimitExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return OverLimitExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionRequestMarshaller.cs
index 753e2708ba38..a2226621e033 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,32 +64,37 @@ public IRequest Marshall(RemovePermissionRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetLabel())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetLabel())
-                    {
-                        context.Writer.WritePropertyName("Label");
-                        context.Writer.Write(publicRequest.Label);
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    writer.WriteObjectEnd();
-                }
+                context.Writer.WritePropertyName("Label");
+                context.Writer.WriteStringValue(publicRequest.Label);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionResponseUnmarshaller.cs
index b4403f002e57..96cd5bef6fa8 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RemovePermissionResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             RemovePermissionResponse response = new RemovePermissionResponse();
 
-
             return response;
         }
 
@@ -61,35 +60,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RequestThrottledExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RequestThrottledExceptionUnmarshaller.cs
index 1e461e36fcd8..3b6c70d5fc34 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RequestThrottledExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/RequestThrottledExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for RequestThrottledException Object
     /// </summary>  
-    public class RequestThrottledExceptionUnmarshaller : IErrorResponseUnmarshaller<RequestThrottledException, JsonUnmarshallerContext>
+    public class RequestThrottledExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<RequestThrottledException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public RequestThrottledException Unmarshall(JsonUnmarshallerContext context)
+        public RequestThrottledException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public RequestThrottledException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public RequestThrottledException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public RequestThrottledException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public RequestThrottledException Unmarshall(JsonUnmarshallerContext context, Ama
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ResourceNotFoundExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ResourceNotFoundExceptionUnmarshaller.cs
index 51796912e7b1..f7613ce2bb09 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ResourceNotFoundExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/ResourceNotFoundExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for ResourceNotFoundException Object
     /// </summary>  
-    public class ResourceNotFoundExceptionUnmarshaller : IErrorResponseUnmarshaller<ResourceNotFoundException, JsonUnmarshallerContext>
+    public class ResourceNotFoundExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<ResourceNotFoundException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public ResourceNotFoundException Unmarshall(JsonUnmarshallerContext context)
+        public ResourceNotFoundException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public ResourceNotFoundException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public ResourceNotFoundException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public ResourceNotFoundException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public ResourceNotFoundException Unmarshall(JsonUnmarshallerContext context, Ama
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestEntryMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestEntryMarshaller.cs
index 1c81cb858710..8209defb08e8 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestEntryMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestEntryMarshaller.cs
@@ -28,8 +28,6 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -51,69 +49,69 @@ public void Marshall(SendMessageBatchRequestEntry requestObject, JsonMarshallerC
             if(requestObject.IsSetDelaySeconds())
             {
                 context.Writer.WritePropertyName("DelaySeconds");
-                context.Writer.Write(requestObject.DelaySeconds.Value);
+                context.Writer.WriteNumberValue(requestObject.DelaySeconds.Value);
             }
 
             if(requestObject.IsSetId())
             {
                 context.Writer.WritePropertyName("Id");
-                context.Writer.Write(requestObject.Id);
+                context.Writer.WriteStringValue(requestObject.Id);
             }
 
             if(requestObject.IsSetMessageAttributes())
             {
                 context.Writer.WritePropertyName("MessageAttributes");
-                context.Writer.WriteObjectStart();
+                context.Writer.WriteStartObject();
                 foreach (var requestObjectMessageAttributesKvp in requestObject.MessageAttributes)
                 {
                     context.Writer.WritePropertyName(requestObjectMessageAttributesKvp.Key);
                     var requestObjectMessageAttributesValue = requestObjectMessageAttributesKvp.Value;
 
-                    context.Writer.WriteObjectStart();
+                    context.Writer.WriteStartObject();
 
                     var marshaller = MessageAttributeValueMarshaller.Instance;
                     marshaller.Marshall(requestObjectMessageAttributesValue, context);
 
-                    context.Writer.WriteObjectEnd();
+                    context.Writer.WriteEndObject();
                 }
-                context.Writer.WriteObjectEnd();
+                context.Writer.WriteEndObject();
             }
 
             if(requestObject.IsSetMessageBody())
             {
                 context.Writer.WritePropertyName("MessageBody");
-                context.Writer.Write(requestObject.MessageBody);
+                context.Writer.WriteStringValue(requestObject.MessageBody);
             }
 
             if(requestObject.IsSetMessageDeduplicationId())
             {
                 context.Writer.WritePropertyName("MessageDeduplicationId");
-                context.Writer.Write(requestObject.MessageDeduplicationId);
+                context.Writer.WriteStringValue(requestObject.MessageDeduplicationId);
             }
 
             if(requestObject.IsSetMessageGroupId())
             {
                 context.Writer.WritePropertyName("MessageGroupId");
-                context.Writer.Write(requestObject.MessageGroupId);
+                context.Writer.WriteStringValue(requestObject.MessageGroupId);
             }
 
             if(requestObject.IsSetMessageSystemAttributes())
             {
                 context.Writer.WritePropertyName("MessageSystemAttributes");
-                context.Writer.WriteObjectStart();
+                context.Writer.WriteStartObject();
                 foreach (var requestObjectMessageSystemAttributesKvp in requestObject.MessageSystemAttributes)
                 {
                     context.Writer.WritePropertyName(requestObjectMessageSystemAttributesKvp.Key);
                     var requestObjectMessageSystemAttributesValue = requestObjectMessageSystemAttributesKvp.Value;
 
-                    context.Writer.WriteObjectStart();
+                    context.Writer.WriteStartObject();
 
                     var marshaller = MessageSystemAttributeValueMarshaller.Instance;
                     marshaller.Marshall(requestObjectMessageSystemAttributesValue, context);
 
-                    context.Writer.WriteObjectEnd();
+                    context.Writer.WriteEndObject();
                 }
-                context.Writer.WriteObjectEnd();
+                context.Writer.WriteEndObject();
             }
 
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestMarshaller.cs
index 9e9f9c633764..74125eb5d2ca 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,42 +64,47 @@ public IRequest Marshall(SendMessageBatchRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetEntries())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("Entries");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestEntriesListValue in publicRequest.Entries)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetEntries())
-                    {
-                        context.Writer.WritePropertyName("Entries");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestEntriesListValue in publicRequest.Entries)
-                        {
-                            context.Writer.WriteObjectStart();
-
-                            var marshaller = SendMessageBatchRequestEntryMarshaller.Instance;
-                            marshaller.Marshall(publicRequestEntriesListValue, context);
-
-                            context.Writer.WriteObjectEnd();
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
+                    context.Writer.WriteStartObject();
 
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
+                    var marshaller = SendMessageBatchRequestEntryMarshaller.Instance;
+                    marshaller.Marshall(publicRequestEntriesListValue, context);
 
-                    writer.WriteObjectEnd();
+                    context.Writer.WriteEndObject();
                 }
+                context.Writer.WriteEndArray();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResponseUnmarshaller.cs
index 40a8f5635c00..a78d7f4feeeb 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,21 +47,21 @@ public class SendMessageBatchResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             SendMessageBatchResponse response = new SendMessageBatchResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Failed", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<BatchResultErrorEntry, BatchResultErrorEntryUnmarshaller>(BatchResultErrorEntryUnmarshaller.Instance);
-                    response.Failed = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<BatchResultErrorEntry, BatchResultErrorEntryUnmarshaller>(BatchResultErrorEntryUnmarshaller.Instance);
+                    response.Failed = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("Successful", targetDepth))
                 {
-                    var unmarshaller = new ListUnmarshaller<SendMessageBatchResultEntry, SendMessageBatchResultEntryUnmarshaller>(SendMessageBatchResultEntryUnmarshaller.Instance);
-                    response.Successful = unmarshaller.Unmarshall(context);
+                    var unmarshaller = new JsonListUnmarshaller<SendMessageBatchResultEntry, SendMessageBatchResultEntryUnmarshaller>(SendMessageBatchResultEntryUnmarshaller.Instance);
+                    response.Successful = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -78,83 +78,84 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("BatchEntryIdsNotDistinct"))
                 {
-                    return BatchEntryIdsNotDistinctExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return BatchEntryIdsNotDistinctExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("BatchRequestTooLong"))
                 {
-                    return BatchRequestTooLongExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return BatchRequestTooLongExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("EmptyBatchRequest"))
                 {
-                    return EmptyBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return EmptyBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidBatchEntryId"))
                 {
-                    return InvalidBatchEntryIdExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidBatchEntryIdExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsAccessDenied"))
                 {
-                    return KmsAccessDeniedExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsAccessDeniedExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsDisabled"))
                 {
-                    return KmsDisabledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsDisabledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsInvalidKeyUsage"))
                 {
-                    return KmsInvalidKeyUsageExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsInvalidKeyUsageExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsInvalidState"))
                 {
-                    return KmsInvalidStateExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsInvalidStateExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsNotFound"))
                 {
-                    return KmsNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsOptInRequired"))
                 {
-                    return KmsOptInRequiredExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsOptInRequiredExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsThrottled"))
                 {
-                    return KmsThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("TooManyEntriesInBatchRequest"))
                 {
-                    return TooManyEntriesInBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return TooManyEntriesInBatchRequestExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResultEntryUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResultEntryUnmarshaller.cs
index 53f7c1698af5..68a6546ed104 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResultEntryUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageBatchResultEntryUnmarshaller.cs
@@ -29,77 +29,67 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for SendMessageBatchResultEntry Object
     /// </summary>  
-    public class SendMessageBatchResultEntryUnmarshaller : IUnmarshaller<SendMessageBatchResultEntry, XmlUnmarshallerContext>, IUnmarshaller<SendMessageBatchResultEntry, JsonUnmarshallerContext>
+    public class SendMessageBatchResultEntryUnmarshaller : IJsonUnmarshaller<SendMessageBatchResultEntry, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
-        /// <returns></returns>
-        SendMessageBatchResultEntry IUnmarshaller<SendMessageBatchResultEntry, XmlUnmarshallerContext>.Unmarshall(XmlUnmarshallerContext context)
-        {
-            throw new NotImplementedException();
-        }
-
-        /// <summary>
-        /// Unmarshaller the response from the service to the response class.
-        /// </summary>  
-        /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns>The unmarshalled object</returns>
-        public SendMessageBatchResultEntry Unmarshall(JsonUnmarshallerContext context)
+        public SendMessageBatchResultEntry Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
             SendMessageBatchResultEntry unmarshalledObject = new SendMessageBatchResultEntry();
             if (context.IsEmptyResponse)
                 return null;
-            context.Read();
-            if (context.CurrentTokenType == JsonToken.Null) 
+            context.Read(ref reader);
+            if (context.CurrentTokenType == JsonTokenType.Null) 
                 return null;
 
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Id", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.Id = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.Id = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfMessageAttributes", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MD5OfMessageAttributes = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MD5OfMessageAttributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfMessageBody", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MD5OfMessageBody = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MD5OfMessageBody = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfMessageSystemAttributes", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MD5OfMessageSystemAttributes = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MD5OfMessageSystemAttributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MessageId", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.MessageId = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.MessageId = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("SequenceNumber", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    unmarshalledObject.SequenceNumber = unmarshaller.Unmarshall(context);
+                    unmarshalledObject.SequenceNumber = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageRequestMarshaller.cs
index ca981e2c36dd..85f8736e5821 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,88 +64,93 @@ public IRequest Marshall(SendMessageRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetDelaySeconds())
+            {
+                context.Writer.WritePropertyName("DelaySeconds");
+                context.Writer.WriteNumberValue(publicRequest.DelaySeconds.Value);
+            }
+
+            if(publicRequest.IsSetMessageAttributes())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("MessageAttributes");
+                context.Writer.WriteStartObject();
+                foreach (var publicRequestMessageAttributesKvp in publicRequest.MessageAttributes)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetDelaySeconds())
-                    {
-                        context.Writer.WritePropertyName("DelaySeconds");
-                        context.Writer.Write(publicRequest.DelaySeconds.Value);
-                    }
-
-                    if(publicRequest.IsSetMessageAttributes())
-                    {
-                        context.Writer.WritePropertyName("MessageAttributes");
-                        context.Writer.WriteObjectStart();
-                        foreach (var publicRequestMessageAttributesKvp in publicRequest.MessageAttributes)
-                        {
-                            context.Writer.WritePropertyName(publicRequestMessageAttributesKvp.Key);
-                            var publicRequestMessageAttributesValue = publicRequestMessageAttributesKvp.Value;
-
-                            context.Writer.WriteObjectStart();
-
-                            var marshaller = MessageAttributeValueMarshaller.Instance;
-                            marshaller.Marshall(publicRequestMessageAttributesValue, context);
-
-                            context.Writer.WriteObjectEnd();
-                        }
-                        context.Writer.WriteObjectEnd();
-                    }
-
-                    if(publicRequest.IsSetMessageBody())
-                    {
-                        context.Writer.WritePropertyName("MessageBody");
-                        context.Writer.Write(publicRequest.MessageBody);
-                    }
-
-                    if(publicRequest.IsSetMessageDeduplicationId())
-                    {
-                        context.Writer.WritePropertyName("MessageDeduplicationId");
-                        context.Writer.Write(publicRequest.MessageDeduplicationId);
-                    }
-
-                    if(publicRequest.IsSetMessageGroupId())
-                    {
-                        context.Writer.WritePropertyName("MessageGroupId");
-                        context.Writer.Write(publicRequest.MessageGroupId);
-                    }
-
-                    if(publicRequest.IsSetMessageSystemAttributes())
-                    {
-                        context.Writer.WritePropertyName("MessageSystemAttributes");
-                        context.Writer.WriteObjectStart();
-                        foreach (var publicRequestMessageSystemAttributesKvp in publicRequest.MessageSystemAttributes)
-                        {
-                            context.Writer.WritePropertyName(publicRequestMessageSystemAttributesKvp.Key);
-                            var publicRequestMessageSystemAttributesValue = publicRequestMessageSystemAttributesKvp.Value;
-
-                            context.Writer.WriteObjectStart();
-
-                            var marshaller = MessageSystemAttributeValueMarshaller.Instance;
-                            marshaller.Marshall(publicRequestMessageSystemAttributesValue, context);
-
-                            context.Writer.WriteObjectEnd();
-                        }
-                        context.Writer.WriteObjectEnd();
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    writer.WriteObjectEnd();
+                    context.Writer.WritePropertyName(publicRequestMessageAttributesKvp.Key);
+                    var publicRequestMessageAttributesValue = publicRequestMessageAttributesKvp.Value;
+
+                    context.Writer.WriteStartObject();
+
+                    var marshaller = MessageAttributeValueMarshaller.Instance;
+                    marshaller.Marshall(publicRequestMessageAttributesValue, context);
+
+                    context.Writer.WriteEndObject();
                 }
+                context.Writer.WriteEndObject();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetMessageBody())
+            {
+                context.Writer.WritePropertyName("MessageBody");
+                context.Writer.WriteStringValue(publicRequest.MessageBody);
             }
 
+            if(publicRequest.IsSetMessageDeduplicationId())
+            {
+                context.Writer.WritePropertyName("MessageDeduplicationId");
+                context.Writer.WriteStringValue(publicRequest.MessageDeduplicationId);
+            }
+
+            if(publicRequest.IsSetMessageGroupId())
+            {
+                context.Writer.WritePropertyName("MessageGroupId");
+                context.Writer.WriteStringValue(publicRequest.MessageGroupId);
+            }
+
+            if(publicRequest.IsSetMessageSystemAttributes())
+            {
+                context.Writer.WritePropertyName("MessageSystemAttributes");
+                context.Writer.WriteStartObject();
+                foreach (var publicRequestMessageSystemAttributesKvp in publicRequest.MessageSystemAttributes)
+                {
+                    context.Writer.WritePropertyName(publicRequestMessageSystemAttributesKvp.Key);
+                    var publicRequestMessageSystemAttributesValue = publicRequestMessageSystemAttributesKvp.Value;
+
+                    context.Writer.WriteStartObject();
+
+                    var marshaller = MessageSystemAttributeValueMarshaller.Instance;
+                    marshaller.Marshall(publicRequestMessageSystemAttributesValue, context);
+
+                    context.Writer.WriteEndObject();
+                }
+                context.Writer.WriteEndObject();
+            }
+
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
+            }
+
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageResponseUnmarshaller.cs
index 4dda0cdc07f7..20332866ca15 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SendMessageResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,39 +47,39 @@ public class SendMessageResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             SendMessageResponse response = new SendMessageResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("MD5OfMessageAttributes", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.MD5OfMessageAttributes = unmarshaller.Unmarshall(context);
+                    response.MD5OfMessageAttributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfMessageBody", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.MD5OfMessageBody = unmarshaller.Unmarshall(context);
+                    response.MD5OfMessageBody = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MD5OfMessageSystemAttributes", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.MD5OfMessageSystemAttributes = unmarshaller.Unmarshall(context);
+                    response.MD5OfMessageSystemAttributes = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("MessageId", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.MessageId = unmarshaller.Unmarshall(context);
+                    response.MessageId = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
                 if (context.TestExpression("SequenceNumber", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.SequenceNumber = unmarshaller.Unmarshall(context);
+                    response.SequenceNumber = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -96,67 +96,68 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidMessageContents"))
                 {
-                    return InvalidMessageContentsExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidMessageContentsExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsAccessDenied"))
                 {
-                    return KmsAccessDeniedExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsAccessDeniedExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsDisabled"))
                 {
-                    return KmsDisabledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsDisabledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsInvalidKeyUsage"))
                 {
-                    return KmsInvalidKeyUsageExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsInvalidKeyUsageExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsInvalidState"))
                 {
-                    return KmsInvalidStateExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsInvalidStateExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsNotFound"))
                 {
-                    return KmsNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsOptInRequired"))
                 {
-                    return KmsOptInRequiredExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsOptInRequiredExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("KmsThrottled"))
                 {
-                    return KmsThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return KmsThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesRequestMarshaller.cs
index 6d16c0bfce5d..7ed40a0e7610 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,40 +64,45 @@ public IRequest Marshall(SetQueueAttributesRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetAttributes())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
+                context.Writer.WritePropertyName("Attributes");
+                context.Writer.WriteStartObject();
+                foreach (var publicRequestAttributesKvp in publicRequest.Attributes)
                 {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetAttributes())
-                    {
-                        context.Writer.WritePropertyName("Attributes");
-                        context.Writer.WriteObjectStart();
-                        foreach (var publicRequestAttributesKvp in publicRequest.Attributes)
-                        {
-                            context.Writer.WritePropertyName(publicRequestAttributesKvp.Key);
-                            var publicRequestAttributesValue = publicRequestAttributesKvp.Value;
-
-                                context.Writer.Write(publicRequestAttributesValue);
-                        }
-                        context.Writer.WriteObjectEnd();
-                    }
-
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
+                    context.Writer.WritePropertyName(publicRequestAttributesKvp.Key);
+                    var publicRequestAttributesValue = publicRequestAttributesKvp.Value;
 
-                    writer.WriteObjectEnd();
+                        context.Writer.WriteStringValue(publicRequestAttributesValue);
                 }
+                context.Writer.WriteEndObject();
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetQueueUrl())
+            {
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesResponseUnmarshaller.cs
index 98ea16704018..10a5e48df5fb 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/SetQueueAttributesResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             SetQueueAttributesResponse response = new SetQueueAttributesResponse();
 
-
             return response;
         }
 
@@ -61,47 +60,48 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAttributeName"))
                 {
-                    return InvalidAttributeNameExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAttributeNameExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAttributeValue"))
                 {
-                    return InvalidAttributeValueExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAttributeValueExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("OverLimit"))
                 {
-                    return OverLimitExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return OverLimitExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskRequestMarshaller.cs
index 49a26c620259..a44843e9e5d1 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,38 +64,43 @@ public IRequest Marshall(StartMessageMoveTaskRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetDestinationArn())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetDestinationArn())
-                    {
-                        context.Writer.WritePropertyName("DestinationArn");
-                        context.Writer.Write(publicRequest.DestinationArn);
-                    }
-
-                    if(publicRequest.IsSetMaxNumberOfMessagesPerSecond())
-                    {
-                        context.Writer.WritePropertyName("MaxNumberOfMessagesPerSecond");
-                        context.Writer.Write(publicRequest.MaxNumberOfMessagesPerSecond.Value);
-                    }
-
-                    if(publicRequest.IsSetSourceArn())
-                    {
-                        context.Writer.WritePropertyName("SourceArn");
-                        context.Writer.Write(publicRequest.SourceArn);
-                    }
+                context.Writer.WritePropertyName("DestinationArn");
+                context.Writer.WriteStringValue(publicRequest.DestinationArn);
+            }
 
-                    writer.WriteObjectEnd();
-                }
+            if(publicRequest.IsSetMaxNumberOfMessagesPerSecond())
+            {
+                context.Writer.WritePropertyName("MaxNumberOfMessagesPerSecond");
+                context.Writer.WriteNumberValue(publicRequest.MaxNumberOfMessagesPerSecond.Value);
+            }
 
-                request.Content = memoryStream.ToArray();
+            if(publicRequest.IsSetSourceArn())
+            {
+                context.Writer.WritePropertyName("SourceArn");
+                context.Writer.WriteStringValue(publicRequest.SourceArn);
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskResponseUnmarshaller.cs
index c5a45a66b65a..15ea13afdedc 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/StartMessageMoveTaskResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -47,15 +47,15 @@ public class StartMessageMoveTaskResponseUnmarshaller : JsonResponseUnmarshaller
         public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext context)
         {
             StartMessageMoveTaskResponse response = new StartMessageMoveTaskResponse();
-
-            context.Read();
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("TaskHandle", targetDepth))
                 {
                     var unmarshaller = StringUnmarshaller.Instance;
-                    response.TaskHandle = unmarshaller.Unmarshall(context);
+                    response.TaskHandle = unmarshaller.Unmarshall(context, ref reader);
                     continue;
                 }
             }
@@ -72,35 +72,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("ResourceNotFoundException"))
                 {
-                    return ResourceNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return ResourceNotFoundExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueRequestMarshaller.cs
index 233810c489ac..9168a4e91687 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,40 +64,45 @@ public IRequest Marshall(TagQueueRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    if(publicRequest.IsSetTags())
-                    {
-                        context.Writer.WritePropertyName("Tags");
-                        context.Writer.WriteObjectStart();
-                        foreach (var publicRequestTagsKvp in publicRequest.Tags)
-                        {
-                            context.Writer.WritePropertyName(publicRequestTagsKvp.Key);
-                            var publicRequestTagsValue = publicRequestTagsKvp.Value;
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
+            }
 
-                                context.Writer.Write(publicRequestTagsValue);
-                        }
-                        context.Writer.WriteObjectEnd();
-                    }
+            if(publicRequest.IsSetTags())
+            {
+                context.Writer.WritePropertyName("Tags");
+                context.Writer.WriteStartObject();
+                foreach (var publicRequestTagsKvp in publicRequest.Tags)
+                {
+                    context.Writer.WritePropertyName(publicRequestTagsKvp.Key);
+                    var publicRequestTagsValue = publicRequestTagsKvp.Value;
 
-                    writer.WriteObjectEnd();
+                        context.Writer.WriteStringValue(publicRequestTagsValue);
                 }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WriteEndObject();
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueResponseUnmarshaller.cs
index 00f08fdbdb6d..77ce8f8f9d52 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TagQueueResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             TagQueueResponse response = new TagQueueResponse();
 
-
             return response;
         }
 
@@ -61,35 +60,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TooManyEntriesInBatchRequestExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TooManyEntriesInBatchRequestExceptionUnmarshaller.cs
index 2691ebff7a98..1e77c59cd625 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TooManyEntriesInBatchRequestExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/TooManyEntriesInBatchRequestExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for TooManyEntriesInBatchRequestException Object
     /// </summary>  
-    public class TooManyEntriesInBatchRequestExceptionUnmarshaller : IErrorResponseUnmarshaller<TooManyEntriesInBatchRequestException, JsonUnmarshallerContext>
+    public class TooManyEntriesInBatchRequestExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<TooManyEntriesInBatchRequestException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public TooManyEntriesInBatchRequestException Unmarshall(JsonUnmarshallerContext context)
+        public TooManyEntriesInBatchRequestException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public TooManyEntriesInBatchRequestException Unmarshall(JsonUnmarshallerContext
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public TooManyEntriesInBatchRequestException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public TooManyEntriesInBatchRequestException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public TooManyEntriesInBatchRequestException Unmarshall(JsonUnmarshallerContext
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UnsupportedOperationExceptionUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UnsupportedOperationExceptionUnmarshaller.cs
index 709b969cbaa4..df9f004a192a 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UnsupportedOperationExceptionUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UnsupportedOperationExceptionUnmarshaller.cs
@@ -29,24 +29,25 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
     /// <summary>
     /// Response Unmarshaller for UnsupportedOperationException Object
     /// </summary>  
-    public class UnsupportedOperationExceptionUnmarshaller : IErrorResponseUnmarshaller<UnsupportedOperationException, JsonUnmarshallerContext>
+    public class UnsupportedOperationExceptionUnmarshaller : IJsonErrorResponseUnmarshaller<UnsupportedOperationException, JsonUnmarshallerContext>
     {
         /// <summary>
         /// Unmarshaller the response from the service to the response class.
         /// </summary>  
         /// <param name="context"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public UnsupportedOperationException Unmarshall(JsonUnmarshallerContext context)
+        public UnsupportedOperationException Unmarshall(JsonUnmarshallerContext context, ref StreamingUtf8JsonReader reader)
         {
-            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse());
+            return this.Unmarshall(context, new Amazon.Runtime.Internal.ErrorResponse(), ref reader);
         }
 
         /// <summary>
@@ -54,10 +55,11 @@ public UnsupportedOperationException Unmarshall(JsonUnmarshallerContext context)
         /// </summary>  
         /// <param name="context"></param>
         /// <param name="errorResponse"></param>
+        /// <param name="reader"></param>
         /// <returns></returns>
-        public UnsupportedOperationException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse)
+        public UnsupportedOperationException Unmarshall(JsonUnmarshallerContext context, Amazon.Runtime.Internal.ErrorResponse errorResponse, ref StreamingUtf8JsonReader reader)
         {
-            context.Read();
+            context.Read(ref reader);
 
             var errorCode = errorResponse.Code;
             var errorType = errorResponse.Type;
@@ -83,7 +85,7 @@ public UnsupportedOperationException Unmarshall(JsonUnmarshallerContext context,
                 errorType, errorCode, errorResponse.RequestId, errorResponse.StatusCode);
         
             int targetDepth = context.CurrentDepth;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
             }
           
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueRequestMarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueRequestMarshaller.cs
index b4e5909b4967..d854cc370d66 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueRequestMarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueRequestMarshaller.cs
@@ -28,8 +28,9 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using System.Buffers;
+using ThirdParty.RuntimeBackports;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -63,37 +64,42 @@ public IRequest Marshall(UntagQueueRequest publicRequest)
             request.HttpMethod = "POST";
 
             request.ResourcePath = "/";
-            using (MemoryStream memoryStream = new MemoryStream())
+#if !NETFRAMEWORK
+            using ArrayPoolBufferWriter<byte> arrayPoolBufferWriter = new ArrayPoolBufferWriter<byte>();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(arrayPoolBufferWriter);
+#else
+            using var memoryStream = new MemoryStream();
+            using Utf8JsonWriter writer = new Utf8JsonWriter(memoryStream);
+#endif
+            writer.WriteStartObject();
+            var context = new JsonMarshallerContext(request, writer);
+            if(publicRequest.IsSetQueueUrl())
             {
-                using (StreamWriter streamWriter = new InvariantCultureStreamWriter(memoryStream))
-                {
-                    JsonWriter writer = new JsonWriter(streamWriter);
-                    writer.Validate = false;
-                    writer.WriteObjectStart();
-                    var context = new JsonMarshallerContext(request, writer);
-                    if(publicRequest.IsSetQueueUrl())
-                    {
-                        context.Writer.WritePropertyName("QueueUrl");
-                        context.Writer.Write(publicRequest.QueueUrl);
-                    }
-
-                    if(publicRequest.IsSetTagKeys())
-                    {
-                        context.Writer.WritePropertyName("TagKeys");
-                        context.Writer.WriteArrayStart();
-                        foreach(var publicRequestTagKeysListValue in publicRequest.TagKeys)
-                        {
-                                context.Writer.Write(publicRequestTagKeysListValue);
-                        }
-                        context.Writer.WriteArrayEnd();
-                    }
+                context.Writer.WritePropertyName("QueueUrl");
+                context.Writer.WriteStringValue(publicRequest.QueueUrl);
+            }
 
-                    writer.WriteObjectEnd();
+            if(publicRequest.IsSetTagKeys())
+            {
+                context.Writer.WritePropertyName("TagKeys");
+                context.Writer.WriteStartArray();
+                foreach(var publicRequestTagKeysListValue in publicRequest.TagKeys)
+                {
+                        context.Writer.WriteStringValue(publicRequestTagKeysListValue);
                 }
-
-                request.Content = memoryStream.ToArray();
+                context.Writer.WriteEndArray();
             }
 
+            writer.WriteEndObject();
+            writer.Flush();
+            // ToArray() must be called here because aspects of sigv4 signing require a byte array
+#if !NETFRAMEWORK
+            request.Content = arrayPoolBufferWriter.WrittenMemory.ToArray();
+#else
+            request.Content = memoryStream.ToArray();
+#endif
+            
+
 
             return request;
         }
diff --git a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueResponseUnmarshaller.cs b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueResponseUnmarshaller.cs
index 6e0faa253a7e..632ea1b03377 100644
--- a/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueResponseUnmarshaller.cs
+++ b/sdk/src/Services/SQS/Generated/Model/Internal/MarshallTransformations/UntagQueueResponseUnmarshaller.cs
@@ -29,8 +29,8 @@
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
 using Amazon.Runtime.Internal.Util;
-using ThirdParty.Json.LitJson;
-
+using System.Text.Json;
+using Amazon.Util;
 #pragma warning disable CS0612,CS0618
 namespace Amazon.SQS.Model.Internal.MarshallTransformations
 {
@@ -48,7 +48,6 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         {
             UntagQueueResponse response = new UntagQueueResponse();
 
-
             return response;
         }
 
@@ -61,35 +60,36 @@ public override AmazonWebServiceResponse Unmarshall(JsonUnmarshallerContext cont
         /// <returns></returns>
         public override AmazonServiceException UnmarshallException(JsonUnmarshallerContext context, Exception innerException, HttpStatusCode statusCode)
         {
-            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(context.Stream);
+            var errorResponse = JsonErrorResponseUnmarshaller.GetInstance().Unmarshall(context, ref reader);
             errorResponse.InnerException = innerException;
             errorResponse.StatusCode = statusCode;
 
             var responseBodyBytes = context.GetResponseBodyBytes();
 
             using (var streamCopy = new MemoryStream(responseBodyBytes))
-
             using (var contextCopy = new JsonUnmarshallerContext(streamCopy, true, context.ResponseData))
             {
+                StreamingUtf8JsonReader readerCopy = new StreamingUtf8JsonReader(streamCopy);
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidAddress"))
                 {
-                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidAddressExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("InvalidSecurity"))
                 {
-                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return InvalidSecurityExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("QueueDoesNotExist"))
                 {
-                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return QueueDoesNotExistExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("RequestThrottled"))
                 {
-                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return RequestThrottledExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
                 if (errorResponse.Code != null && errorResponse.Code.Equals("UnsupportedOperation"))
                 {
-                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse);
+                    return UnsupportedOperationExceptionUnmarshaller.Instance.Unmarshall(contextCopy, errorResponse, ref readerCopy);
                 }
             }
             var errorCode = errorResponse.Code;
diff --git a/sdk/test/UnitTests/Custom/Marshalling/ErrorUnmarshallingTests.cs b/sdk/test/UnitTests/Custom/Marshalling/ErrorUnmarshallingTests.cs
index 473a765c59bd..ba39f137b4ce 100644
--- a/sdk/test/UnitTests/Custom/Marshalling/ErrorUnmarshallingTests.cs
+++ b/sdk/test/UnitTests/Custom/Marshalling/ErrorUnmarshallingTests.cs
@@ -17,6 +17,7 @@
 using Amazon.Runtime;
 using Amazon.Runtime.Internal;
 using Amazon.Runtime.Internal.Transform;
+using Amazon.Runtime.Internal.Util;
 using Amazon.Util;
 using AWSSDK_DotNet.UnitTests;
 using AWSSDK_DotNet.UnitTests.TestTools;
@@ -163,8 +164,10 @@ private ErrorResponse GetJsonErrorResponse(string body, string xAmzErrorTypeValu
 
             webResponse.Headers.Add("Content-Length", UTF8Encoding.UTF8.GetBytes(body).Length.ToString());
 
-            var context = new JsonUnmarshallerContext(AWSSDK_DotNet.UnitTests.Utils.CreateStreamFromString(body), true, webResponse);
-            return new JsonErrorResponseUnmarshaller().Unmarshall(context);
+            var stream = AWSSDK_DotNet.UnitTests.Utils.CreateStreamFromString(body);
+            var context = new JsonUnmarshallerContext(stream, true, webResponse);
+            var reader = new StreamingUtf8JsonReader(context.Stream);
+            return new JsonErrorResponseUnmarshaller().Unmarshall(context, ref reader);
         }
 
         private void RunXmlErrorUnmarshallingTest(string body, string expectedMessage, string expectedCode, ErrorType expectedType)
@@ -186,7 +189,7 @@ private ErrorResponse GetXmlErrorResponse(string body)
             webResponse.Headers.Add("Content-Length", UTF8Encoding.UTF8.GetBytes(body).Length.ToString());
 
             var context = new XmlUnmarshallerContext(AWSSDK_DotNet.UnitTests.Utils.CreateStreamFromString(body), true, webResponse);
-            return new ErrorResponseUnmarshaller().Unmarshall(context);
+            return new XmlErrorResponseUnmarshaller().Unmarshall(context);
         }
     }
 }
diff --git a/sdk/test/UnitTests/Custom/Marshalling/SimpleTypeUnmarshallerTests.cs b/sdk/test/UnitTests/Custom/Marshalling/SimpleTypeUnmarshallerTests.cs
index fcd16e1d83d1..7d4ce91c0842 100644
--- a/sdk/test/UnitTests/Custom/Marshalling/SimpleTypeUnmarshallerTests.cs
+++ b/sdk/test/UnitTests/Custom/Marshalling/SimpleTypeUnmarshallerTests.cs
@@ -12,11 +12,14 @@
  * express or implied. See the License for the specific language governing
  * permissions and limitations under the License.
  */
+using System.Text.Json;
 using Amazon.Runtime.Internal.Transform;
+using Amazon.Runtime.Internal.Util;
 using AWSSDK_DotNet.UnitTests;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using System;
 using System.IO;
+using Amazon.KeyManagementService.Model;
 
 namespace AWSSDK.UnitTests
 {
@@ -60,48 +63,50 @@ public void TestJsonUnmarshalling()
 
         private Model UnmarshallModel(string json)
         {
-            var context = new JsonUnmarshallerContext(Utils.CreateStreamFromString(json), false, null);
-            context.Read();
+            var stream = Utils.CreateStreamFromString(json);
+            JsonUnmarshallerContext context = new JsonUnmarshallerContext(stream, false, null);
+            var reader = new StreamingUtf8JsonReader(stream);
+            context.Read(ref reader);
             int targetDepth = context.CurrentDepth;
             var model = new Model();
             bool isSetPriority = false, isSetReservoirQuotaTTL = false, isSetStartTimeISO8601 = false, 
                 isSetStartTimeEpoch = false, isSetStartTimeRFC822 = false, isSetStream = false;
-            while (context.ReadAtDepth(targetDepth))
+            while (context.ReadAtDepth(targetDepth, ref reader))
             {
                 if (context.TestExpression("Priority", targetDepth))
                 {
                     var unmarshaller = NullableIntUnmarshaller.Instance;
-                    model.Priority = unmarshaller.Unmarshall(context);
+                    model.Priority = unmarshaller.Unmarshall(context, ref reader);
                     isSetPriority = true;
                 }
                 if (context.TestExpression("ReservoirQuotaTTL", targetDepth))
                 {
                     var unmarshaller = NullableDateTimeUnmarshaller.Instance;
-                    model.ReservoirQuotaTTL = unmarshaller.Unmarshall(context);
+                    model.ReservoirQuotaTTL = unmarshaller.Unmarshall(context, ref reader);
                     isSetReservoirQuotaTTL = true;
                 }
                 if (context.TestExpression("StartTimeISO8601", targetDepth))
                 {
                     var unmarshaller = DateTimeUnmarshaller.Instance;
-                    model.StartTimeISO8601 = unmarshaller.Unmarshall(context);
+                    model.StartTimeISO8601 = unmarshaller.Unmarshall(context, ref reader);
                     isSetStartTimeISO8601 = true;
                 }
                 if (context.TestExpression("StartTimeEpoch", targetDepth))
                 {
                     var unmarshaller = DateTimeUnmarshaller.Instance;
-                    model.StartTimeEpoch = unmarshaller.Unmarshall(context);
+                    model.StartTimeEpoch = unmarshaller.Unmarshall(context, ref reader);
                     isSetStartTimeEpoch = true;
                 }
                 if (context.TestExpression("StartTimeRFC822", targetDepth))
                 {
                     var unmarshaller = DateTimeUnmarshaller.Instance;
-                    model.StartTimeRFC822 = unmarshaller.Unmarshall(context);
+                    model.StartTimeRFC822 = unmarshaller.Unmarshall(context, ref reader);
                     isSetStartTimeRFC822 = true;
                 }
                 if (context.TestExpression("Stream", targetDepth))
                 {
                     var unmarshaller = MemoryStreamUnmarshaller.Instance;
-                    model.Stream = unmarshaller.Unmarshall(context);
+                    model.Stream = unmarshaller.Unmarshall(context, ref reader);
 
                     if (model.Stream != null)
                     {
diff --git a/sdk/test/UnitTests/Custom/Marshalling/StreamingUtf8JsonReaderTests.cs b/sdk/test/UnitTests/Custom/Marshalling/StreamingUtf8JsonReaderTests.cs
new file mode 100644
index 000000000000..2d6d80a54492
--- /dev/null
+++ b/sdk/test/UnitTests/Custom/Marshalling/StreamingUtf8JsonReaderTests.cs
@@ -0,0 +1,215 @@
+using AWSSDK_DotNet.CommonTest.Utils;
+using AWSSDK_DotNet.UnitTests;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using System.IO;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Text.Json;
+using System.Threading.Tasks;
+using Amazon.Runtime.Internal.Util;
+using Amazon.EC2.Model;
+using Amazon;
+namespace AWSSDK.UnitTests
+{
+    /// <summary>
+    /// Protocol tests already exists to test the marshalling and unmarshalling of request and responses in json, but they don't test very
+    /// large payloads, which would trigger the logic for getting more bytes from the stream. 
+    /// This class just tests the wrapper class StreamingUtf8JsonReader. 
+    /// </summary>
+    [TestClass]
+    public class StreamingUtf8JsonReaderTests
+    {
+        [TestMethod]
+        public void SkipsUtf8BOM()
+        {
+            // we can't use reflection to access the private fields of StreamingUtf8JsonReader since it is a ref struct so we have to test it this way.
+            var a = Convert.ToByte('{');
+            var b = Convert.ToByte('x');
+            var c = Convert.ToByte(':');
+            var d = Convert.ToByte('y');
+            var e = Convert.ToByte('}');
+
+            byte[] payload = new byte[] { 0xEF, 0xBB, 0xBF, a, b, c, d, e };
+            MemoryStream stream = new MemoryStream(payload);
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(stream);
+            while (reader.Read())
+            {
+                Assert.IsTrue(reader.Reader.TokenType == JsonTokenType.StartObject);
+                return;
+            }
+        }
+
+        // This method tests that if the json token starts in one buffer but continues into the next buffer
+        // the reader can handle parsing it correctly.
+        [TestMethod]
+        public void StreamingUtf8JsonReaderHandlesJsonTokenThatSpansMultipleBuffers()
+        {
+            // Arrange
+            // here we're creating a json string that is greater than the default buffer size to test the GetMoreBytesFromStream logic
+            var sb = new StringBuilder();
+            sb.Append("{ \"key\": \"");
+            var size = 4096 + 500;
+            sb.Append(new string('x', size));
+            sb.Append("\" }");
+            string largeJson = sb.ToString();
+
+            byte[] payload = Encoding.UTF8.GetBytes(largeJson);
+            using (var stream = new MemoryStream(payload))
+            {
+                var reader = new StreamingUtf8JsonReader(stream);
+                string key = null, value = null;
+
+                while (reader.Read())
+                {
+                    if (reader.Reader.TokenType == JsonTokenType.PropertyName)
+                    {
+                        key = reader.Reader.GetString();
+                    }
+                    else if (reader.Reader.TokenType == JsonTokenType.String)
+                    {
+                        value = reader.Reader.GetString();
+                    }
+                }
+                Assert.AreEqual<string>("key", key);
+                Assert.AreEqual<string>(new string('x', size), value);
+            }
+        }
+
+        [TestMethod]
+        public void StreamingUtf8JsonReaderHandlesNormalPayload()
+        {
+            // Arrange
+            var sb = new StringBuilder();
+            sb.Append("{ \"key\": \"");
+            sb.Append(new string('x', 1));
+            sb.Append("\" }");
+            string largeJson = sb.ToString();
+
+            byte[] payload = Encoding.UTF8.GetBytes(largeJson);
+            using (var stream = new MemoryStream(payload))
+            {
+                var reader = new StreamingUtf8JsonReader(stream);
+                string key = null, value = null;
+
+                while (reader.Read())
+                {
+                    if (reader.Reader.TokenType == JsonTokenType.PropertyName)
+                    {
+                        key = reader.Reader.GetString();
+                    }
+                    else if (reader.Reader.TokenType == JsonTokenType.String)
+                    {
+                        value = reader.Reader.GetString();
+                    }
+                }
+                Assert.AreEqual<string>("key", key);
+                Assert.AreEqual<string>(new string('x', 1), value);
+            }
+        }
+
+        [TestMethod]
+        public void StreamingUtf8JsonReaderHandlesExactBufferSize()
+        {
+            var sb = new StringBuilder();
+            // everything other than the 'x' is 13 bytes
+            var size = 4096 - 13;
+            sb.Append("{ \"key\": \"");
+            sb.Append(new string('x', size));
+            sb.Append("\" }");
+            string largeJson = sb.ToString();
+            Assert.AreEqual<int>(4096, Encoding.UTF8.GetByteCount(largeJson));
+
+
+            byte[] payload = Encoding.UTF8.GetBytes(largeJson);
+            using (var stream = new MemoryStream(payload))
+            {
+                var reader = new StreamingUtf8JsonReader(stream);
+                string key = null, value = null;
+
+                while (reader.Read())
+                {
+                    if (reader.Reader.TokenType == JsonTokenType.PropertyName)
+                    {
+                        key = reader.Reader.GetString();
+                    }
+                    else if (reader.Reader.TokenType == JsonTokenType.String)
+                    {
+                        value = reader.Reader.GetString();
+                    }
+                }
+                Assert.AreEqual<string>("key", key);
+                Assert.AreEqual<string>(new string('x', size), value);
+            }
+        }
+
+        [TestMethod]
+        public void StreamingUtf8JsonReaderHandlesBufferSizePlusOne()
+        {
+            var sb = new StringBuilder();
+            // everything other than the 'x' is 13 bytes
+            var size = 4096 - 13 + 1;
+            sb.Append("{ \"key\": \"");
+            sb.Append(new string('x', size));
+            sb.Append("\" }");
+            string largeJson = sb.ToString();
+
+
+            byte[] payload = Encoding.UTF8.GetBytes(largeJson);
+            using (var stream = new MemoryStream(payload))
+            {
+                var reader = new StreamingUtf8JsonReader(stream);
+                string key = null, value = null;
+
+                while (reader.Read())
+                {
+                    if (reader.Reader.TokenType == JsonTokenType.PropertyName)
+                    {
+                        key = reader.Reader.GetString();
+                    }
+                    else if (reader.Reader.TokenType == JsonTokenType.String)
+                    {
+                        value = reader.Reader.GetString();
+                    }
+                }
+                Assert.AreEqual<string>("key", key);
+                Assert.AreEqual<string>(new string('x', size), value);
+            }
+        }
+
+        [TestMethod]
+        public void StreamingUtf8JsonReaderHandlesBufferSizeMinusOne()
+        {
+            var sb = new StringBuilder();
+            // everything other than the 'x' is 13 bytes
+            var size = 4096 - 13 - 1;
+            sb.Append("{ \"key\": \"");
+            sb.Append(new string('x', size));
+            sb.Append("\" }");
+            string largeJson = sb.ToString();
+
+
+            byte[] payload = Encoding.UTF8.GetBytes(largeJson);
+            using (var stream = new MemoryStream(payload))
+            {
+                var reader = new StreamingUtf8JsonReader(stream);
+                string key = null, value = null;
+
+                while (reader.Read())
+                {
+                    if (reader.Reader.TokenType == JsonTokenType.PropertyName)
+                    {
+                        key = reader.Reader.GetString();
+                    }
+                    else if (reader.Reader.TokenType == JsonTokenType.String)
+                    {
+                        value = reader.Reader.GetString();
+                    }
+                }
+                Assert.AreEqual<string>("key", key);
+                Assert.AreEqual<string>(new string('x', size), value);
+            }
+        }
+    }
+}
diff --git a/sdk/test/UnitTests/Custom/Runtime/Documents/DocumentMarshallingTests.cs b/sdk/test/UnitTests/Custom/Runtime/Documents/DocumentMarshallingTests.cs
index 61739c8eb031..4431261b5982 100644
--- a/sdk/test/UnitTests/Custom/Runtime/Documents/DocumentMarshallingTests.cs
+++ b/sdk/test/UnitTests/Custom/Runtime/Documents/DocumentMarshallingTests.cs
@@ -20,7 +20,8 @@
 using Amazon.Runtime.Documents.Internal.Transform;
 using Amazon.Runtime.Internal.Transform;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
-using ThirdParty.Json.LitJson;
+using System.Text.Json;
+using Amazon.Runtime.Internal.Util;
 
 namespace AWSSDK.UnitTests
 {
@@ -204,27 +205,27 @@ public void BasicUnmarshalTest()
         
         private string Marshall(Document d)
         {
-            var buffer = new StringBuilder();
-            var jsonWriter = new JsonWriter(buffer);
-            jsonWriter.WriteObjectStart();
+            var stream = new MemoryStream();
+            var jsonWriter = new Utf8JsonWriter(stream);
+            jsonWriter.WriteStartObject();
             jsonWriter.WritePropertyName("document");
             DocumentMarshaller.Instance.Write(jsonWriter, d);
-            jsonWriter.WriteObjectEnd();
-            
-            return buffer.ToString();
+            jsonWriter.WriteEndObject();
+            jsonWriter.Flush();
+            return Encoding.UTF8.GetString(stream.ToArray());
         }
 
         private Document Unmarshall(string json)
         {
             var ms = new MemoryStream(Encoding.UTF8.GetBytes(json));
             var context = new JsonUnmarshallerContext(ms, false,null);
-            
+            StreamingUtf8JsonReader reader = new StreamingUtf8JsonReader(ms);
             // simulate reading property name
-            context.Read();
-            context.ReadAtDepth(context.CurrentDepth);
+            context.Read(ref reader);
+            context.ReadAtDepth(context.CurrentDepth, ref reader);
             var temp = context.TestExpression("document", context.CurrentDepth);
             
-            return DocumentUnmarshaller.Instance.Unmarshall(context);
+            return DocumentUnmarshaller.Instance.Unmarshall(context, ref reader);
         }
     }
 }
\ No newline at end of file
diff --git a/sdk/test/UnitTests/Custom/TestTools/JsonSampleGenerator.cs b/sdk/test/UnitTests/Custom/TestTools/JsonSampleGenerator.cs
index 0198a77543cb..8bcbdb4b4006 100644
--- a/sdk/test/UnitTests/Custom/TestTools/JsonSampleGenerator.cs
+++ b/sdk/test/UnitTests/Custom/TestTools/JsonSampleGenerator.cs
@@ -10,6 +10,8 @@
 using Amazon.Runtime.Documents;
 using Amazon.Runtime.Documents.Internal.Transform;
 using Amazon.Util;
+using System.Text.Json;
+using System.IO;
 
 namespace AWSSDK_DotNet.UnitTests.TestTools
 {
@@ -29,16 +31,16 @@ public JsonSampleGenerator(ServiceModel model, Shape rootStructure)
         public string Execute()
         {
             this._tcr = new TypeCircularReference<string>();
-            JsonWriter writer = new JsonWriter();
-            writer.PrettyPrint = true;
+            var stream = new MemoryStream();
+            Utf8JsonWriter writer = new Utf8JsonWriter(stream);
 
             WriteStructure(writer, null, this._rootStructure);
-
-            var json = writer.ToString();
+            writer.Flush();
+            var json = Encoding.UTF8.GetString(stream.ToArray());
             return json;
         }
 
-        private void Write(JsonWriter writer, Member member, Shape shape)
+        private void Write(Utf8JsonWriter writer, Member member, Shape shape)
         {
             if (shape.IsDocument)
             {
@@ -57,32 +59,32 @@ private void Write(JsonWriter writer, Member member, Shape shape)
             else if (shape.IsEnum)
             {
                 var enumerationWrapper = this._model.Enumerations(true).First(x => x.Name == shape.Name);
-                writer.Write(enumerationWrapper.EnumerationValues.ElementAt(0).MarshallName);
+                writer.WriteStringValue(enumerationWrapper.EnumerationValues.ElementAt(0).MarshallName);
             }
             else if (shape.IsString)
-                writer.Write(shape.Name + "_Value");
+                writer.WriteStringValue(shape.Name + "_Value");
             else if (shape.IsInt)
-                writer.Write(int.MaxValue);
+                writer.WriteNumberValue(int.MaxValue);
             else if (shape.IsLong)
-                writer.Write(long.MaxValue);
+                writer.WriteNumberValue(long.MaxValue);
             else if (shape.IsDouble)
-                writer.Write(double.MaxValue);
+                writer.WriteNumberValue(double.MaxValue);
             else if (shape.IsFloat)
-                writer.Write(float.MaxValue);
-            else if (shape.IsTimeStamp)
+                writer.WriteNumberValue(float.MaxValue);
+            else if (shape.IsDateTime)
             {
-                writer.Write(ValidatorUtils.GetTestDate(member, shape));
+                writer.WriteStringValue(ValidatorUtils.GetTestDate(member, shape));
             }
             else if (shape.IsBoolean)
-                writer.Write(true);
+                writer.WriteBooleanValue(true);
             else if (shape.IsMemoryStream)
-                writer.Write(Constants.DEFAULT_BLOB_ENCODED);
+                writer.WriteStringValue(Constants.DEFAULT_BLOB_ENCODED);
             else
                 throw new Exception("Unknown Type for shape " + shape.Name);
         }
 
 
-        private void WriteStructure(JsonWriter writer, Member memberWithComplexShape, Shape structure)
+        private void WriteStructure(Utf8JsonWriter writer, Member memberWithComplexShape, Shape structure)
         {
             if (structure.IsDocument)
             {
@@ -94,8 +96,8 @@ private void WriteStructure(JsonWriter writer, Member memberWithComplexShape, Sh
             if (!pushed)
             {
                 // Circular reference found. Closing the structure
-                writer.WriteObjectStart();
-                writer.WriteObjectEnd();
+                writer.WriteStartObject();
+                writer.WriteEndObject();
                 return;
             }
 
@@ -105,7 +107,7 @@ private void WriteStructure(JsonWriter writer, Member memberWithComplexShape, Sh
                 return;
             }
 
-            writer.WriteObjectStart();
+            writer.WriteStartObject();
 
             foreach (var member in structure.Members)
             {
@@ -116,21 +118,21 @@ private void WriteStructure(JsonWriter writer, Member memberWithComplexShape, Sh
                     string.Equals(member.OverrideDataType.Unmarshaller, "NullableDateTimeEpochLongMillisecondsUnmarshaller"))
                 )
                 {
-                    writer.Write(ValidatorUtils.GetTestEpochTime().TotalMilliseconds);
+                    writer.WriteNumberValue(ValidatorUtils.GetTestEpochTime().TotalMilliseconds);
                 }
                 else if (member.OverrideDataType != null && (
                     string.Equals(member.OverrideDataType.Unmarshaller, "Amazon.Runtime.Internal.Transform.DateTimeUnmarshaller") || 
                     string.Equals(member.OverrideDataType.Unmarshaller, "Amazon.Runtime.Internal.Transform.NullableDateTimeUnmarshaller"))
                 )
                 {
-                    writer.Write(Constants.DEFAULT_DATE.ToString(AWSSDKUtils.ISO8601DateFormat, CultureInfo.InvariantCulture));
+                    writer.WriteStringValue(Constants.DEFAULT_DATE.ToString(AWSSDKUtils.ISO8601DateFormat, CultureInfo.InvariantCulture));
                 }
                 else if (member.OverrideDataType != null && (
                     string.Equals(member.OverrideDataType.Unmarshaller, "Amazon.Runtime.Internal.Transform.DecimalUnmarshaller") ||
                     string.Equals(member.OverrideDataType.Unmarshaller, "Amazon.Runtime.Internal.Transform.NullableDecimalUnmarshaller"))
                 )
                 {
-                    writer.Write(Constants.DEFAULT_DECIMAL.ToString(CultureInfo.InvariantCulture));
+                    writer.WriteStringValue(Constants.DEFAULT_DECIMAL.ToString(CultureInfo.InvariantCulture));
                 }
                 else
                 {
@@ -138,17 +140,17 @@ private void WriteStructure(JsonWriter writer, Member memberWithComplexShape, Sh
                 }
             }
 
-            writer.WriteObjectEnd();
+            writer.WriteEndObject();
 
             if (pushed)
                 this._tcr.Pop();
         }
 
 
-        private void WriteArray(JsonWriter writer, Member member, Shape array)
+        private void WriteArray(Utf8JsonWriter writer, Member member, Shape array)
         {
 
-            writer.WriteArrayStart();
+            writer.WriteStartArray();
 
             var listShape = array.ListShape;
             if (!listShape.IsStructure || !this._tcr.Contains(listShape.Name))
@@ -159,13 +161,13 @@ private void WriteArray(JsonWriter writer, Member member, Shape array)
                 }
             }
 
-            writer.WriteArrayEnd();
+            writer.WriteEndArray();
         }
 
-        private void WriteMap(JsonWriter writer, Member member, Shape map)
+        private void WriteMap(Utf8JsonWriter writer, Member member, Shape map)
         {
 
-            writer.WriteObjectStart();
+            writer.WriteStartObject();
 
             var mapShape = map.ValueShape;
             if (!mapShape.IsStructure || !this._tcr.Contains(mapShape.Name))
@@ -177,7 +179,7 @@ private void WriteMap(JsonWriter writer, Member member, Shape map)
                 }
             }
 
-            writer.WriteObjectEnd();
+            writer.WriteEndObject();
         }
 
         /// <summary>