diff --git a/src/Orchard.Web/Orchard.Web.csproj b/src/Orchard.Web/Orchard.Web.csproj
index b9241408c2..e495d1f9c5 100644
--- a/src/Orchard.Web/Orchard.Web.csproj
+++ b/src/Orchard.Web/Orchard.Web.csproj
@@ -79,17 +79,14 @@
     <Reference Include="Microsoft.Web.Infrastructure, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <HintPath>..\packages\Microsoft.Web.Infrastructure.1.0.0.0\lib\net40\Microsoft.Web.Infrastructure.dll</HintPath>
     </Reference>
-    <Reference Include="Mono.Security, Version=4.0.0.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756, processorArchitecture=MSIL">
-      <HintPath>..\packages\Npgsql.2.2.3\lib\net45\Mono.Security.dll</HintPath>
-    </Reference>
     <Reference Include="MySql.Data, Version=6.7.9.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d, processorArchitecture=MSIL">
       <HintPath>..\packages\MySql.Data.6.7.9\lib\net45\MySql.Data.dll</HintPath>
     </Reference>
     <Reference Include="Newtonsoft.Json, Version=13.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
       <HintPath>..\packages\Newtonsoft.Json.13.0.1\lib\net45\Newtonsoft.Json.dll</HintPath>
     </Reference>
-    <Reference Include="Npgsql, Version=2.2.3.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
-      <HintPath>..\packages\Npgsql.2.2.3\lib\net45\Npgsql.dll</HintPath>
+    <Reference Include="Npgsql, Version=4.0.16.0, Culture=neutral, PublicKeyToken=5d8b90d52f46fda7, processorArchitecture=MSIL">
+      <HintPath>..\packages\Npgsql.4.0.16\lib\net451\Npgsql.dll</HintPath>
     </Reference>
     <Reference Include="NuGet.Core, Version=1.1.0.0, Culture=neutral, processorArchitecture=MSIL">
       <HintPath>..\packages\Orchard.NuGet.Core.1.1.0.0\lib\NuGet.Core.dll</HintPath>
@@ -98,6 +95,9 @@
       <HintPath>..\packages\Owin.1.0\lib\net40\Owin.dll</HintPath>
     </Reference>
     <Reference Include="System" />
+    <Reference Include="System.Buffers, Version=4.0.2.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.Buffers.4.4.0\lib\netstandard2.0\System.Buffers.dll</HintPath>
+    </Reference>
     <Reference Include="System.Data" />
     <Reference Include="System.ComponentModel.DataAnnotations">
       <RequiredTargetFramework>3.5</RequiredTargetFramework>
@@ -107,7 +107,23 @@
       <HintPath>..\..\lib\sqlce\System.Data.SqlServerCe.dll</HintPath>
       <Private>True</Private>
     </Reference>
+    <Reference Include="System.Memory, Version=4.0.1.1, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.Memory.4.5.3\lib\netstandard2.0\System.Memory.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Numerics" />
+    <Reference Include="System.Numerics.Vectors, Version=4.1.3.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.Numerics.Vectors.4.4.0\lib\net46\System.Numerics.Vectors.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Runtime.CompilerServices.Unsafe, Version=4.0.4.1, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.Runtime.CompilerServices.Unsafe.4.5.2\lib\netstandard2.0\System.Runtime.CompilerServices.Unsafe.dll</HintPath>
+    </Reference>
     <Reference Include="System.ServiceModel" />
+    <Reference Include="System.Threading.Tasks.Extensions, Version=4.2.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.Threading.Tasks.Extensions.4.5.2\lib\netstandard2.0\System.Threading.Tasks.Extensions.dll</HintPath>
+    </Reference>
+    <Reference Include="System.ValueTuple, Version=4.0.3.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.ValueTuple.4.5.0\lib\net47\System.ValueTuple.dll</HintPath>
+    </Reference>
     <Reference Include="System.Web.ApplicationServices" />
     <Reference Include="System.Web.DynamicData" />
     <Reference Include="System.Web.Entity" />
diff --git a/src/Orchard.Web/packages.config b/src/Orchard.Web/packages.config
index de35a60b13..229f69c805 100644
--- a/src/Orchard.Web/packages.config
+++ b/src/Orchard.Web/packages.config
@@ -14,7 +14,13 @@
   <package id="Microsoft.Web.Infrastructure" version="1.0.0.0" targetFramework="net48" />
   <package id="MySql.Data" version="6.7.9" targetFramework="net48" />
   <package id="Newtonsoft.Json" version="13.0.1" targetFramework="net48" />
-  <package id="Npgsql" version="2.2.3" targetFramework="net48" />
+  <package id="Npgsql" version="4.0.16" targetFramework="net48" />
   <package id="Orchard.NuGet.Core" version="1.1.0.0" targetFramework="net48" />
   <package id="Owin" version="1.0" targetFramework="net48" />
+  <package id="System.Buffers" version="4.4.0" targetFramework="net48" />
+  <package id="System.Memory" version="4.5.3" targetFramework="net48" />
+  <package id="System.Numerics.Vectors" version="4.4.0" targetFramework="net48" />
+  <package id="System.Runtime.CompilerServices.Unsafe" version="4.5.2" targetFramework="net48" />
+  <package id="System.Threading.Tasks.Extensions" version="4.5.2" targetFramework="net48" />
+  <package id="System.ValueTuple" version="4.5.0" targetFramework="net48" />
 </packages>
\ No newline at end of file