diff --git a/build/common.targets b/build/common.targets
index cba06cbd2..18feca830 100644
--- a/build/common.targets
+++ b/build/common.targets
@@ -7,7 +7,7 @@ repo. It imports the other MSBuild files as needed.
 <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <!--set general build properties -->
-    <Version>3.18.6</Version>
+    <Version>4.0.0</Version>
     <Product>SMAPI</Product>
     <LangVersion>latest</LangVersion>
     <AssemblySearchPaths>$(AssemblySearchPaths);{GAC}</AssemblySearchPaths>
diff --git a/docs/release-notes.md b/docs/release-notes.md
index 975f01e49..3413ae041 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -1,20 +1,22 @@
 ← [README](README.md)
 
 # Release notes
-## Upcoming release for Stardew Valley 1.6
+## 4.0.0
+Released 19 March 2024 for Stardew Valley 1.6.0 or later. See [release highlights](https://www.patreon.com/posts/100388693).
+
 * For players:
   * Updated for Stardew Valley 1.6.
   * Added support for overriding SMAPI configuration per `Mods` folder (thanks to Shockah!).
   * Improved performance.
-  * Improved compatibility rewriting to handle more cases (thanks to SinZ!).
-  * Removed the bundled `ErrorHandler` mod (now integrated into Stardew Valley 1.6).
+  * Improved compatibility rewriting to handle more cases (thanks to SinZ for his contributions!).
+  * Removed the bundled `ErrorHandler` mod, which is now integrated into Stardew Valley 1.6.
   * Removed obsolete console commands: `list_item_types` (no longer needed) and `player_setimmunity` (broke in 1.6 and rarely used).
   * Removed support for seamlessly updating from SMAPI 2.11.3 and earlier (released in 2019).  
     _If needed, you can update to SMAPI 3.18.0 first and then install the latest version._
 
 * For mod authors:
   * Updated to .NET 6.
-  * Added `RenderingStep` and `RenderedStep` events, which let you handle a specific step in the game's render cycle.
+  * Added [`RenderingStep` and `RenderedStep` events](https://stardewvalleywiki.com/Modding:Modder_Guide/APIs/Events#Display.RenderingStep), which let you handle a specific step in the game's render cycle.
   * Added support for [custom update manifests](https://stardewvalleywiki.com/Modding:Modder_Guide/APIs/Update_checks#Custom_update_manifest) (thanks to Jamie Taylor!).
   * Removed all deprecated APIs.
   * SMAPI no longer intercepts output written to the console. Mods which directly access `Console` will be listed under mod warnings.
@@ -27,8 +29,7 @@
   * Fixed update check for mods with a prerelease version tag not recognized by the ModDrop API. SMAPI now parses the version itself if needed.
 
 * For SMAPI developers:
-  * Improved compatibility rewriters.
-  * Added `LogTechnicalDetailsForBrokenMods` option in `smapi-internal/config.json` which adds more technical info to the SMAPI log when a mod is broken. This is mainly useful for creating compatibility rewriters.
+  * Added `LogTechnicalDetailsForBrokenMods` option in `smapi-internal/config.json`, which adds more technical info to the SMAPI log when a mod is broken. This is mainly useful for creating compatibility rewriters.
 
 ## 3.18.6
 Released 05 October 2023 for Stardew Valley 1.5.6 or later.
diff --git a/src/SMAPI.Mods.ConsoleCommands/manifest.json b/src/SMAPI.Mods.ConsoleCommands/manifest.json
index a97124e50..8267c9ae5 100644
--- a/src/SMAPI.Mods.ConsoleCommands/manifest.json
+++ b/src/SMAPI.Mods.ConsoleCommands/manifest.json
@@ -1,9 +1,9 @@
 {
     "Name": "Console Commands",
     "Author": "SMAPI",
-    "Version": "3.18.6",
+    "Version": "4.0.0",
     "Description": "Adds SMAPI console commands that let you manipulate the game.",
     "UniqueID": "SMAPI.ConsoleCommands",
     "EntryDll": "ConsoleCommands.dll",
-    "MinimumApiVersion": "3.18.6"
+    "MinimumApiVersion": "4.0.0"
 }
diff --git a/src/SMAPI.Mods.SaveBackup/manifest.json b/src/SMAPI.Mods.SaveBackup/manifest.json
index 94a1ce79c..e45015093 100644
--- a/src/SMAPI.Mods.SaveBackup/manifest.json
+++ b/src/SMAPI.Mods.SaveBackup/manifest.json
@@ -1,9 +1,9 @@
 {
     "Name": "Save Backup",
     "Author": "SMAPI",
-    "Version": "3.18.6",
+    "Version": "4.0.0",
     "Description": "Automatically backs up all your saves once per day into its folder.",
     "UniqueID": "SMAPI.SaveBackup",
     "EntryDll": "SaveBackup.dll",
-    "MinimumApiVersion": "3.18.6"
+    "MinimumApiVersion": "4.0.0"
 }
diff --git a/src/SMAPI/Constants.cs b/src/SMAPI/Constants.cs
index ee33045b4..9d836b3b9 100644
--- a/src/SMAPI/Constants.cs
+++ b/src/SMAPI/Constants.cs
@@ -49,7 +49,7 @@ internal static class EarlyConstants
         internal static int? LogScreenId { get; set; }
 
         /// <summary>SMAPI's current raw semantic version.</summary>
-        internal static string RawApiVersion = "3.18.6";
+        internal static string RawApiVersion = "4.0.0";
     }
 
     /// <summary>Contains SMAPI's constants and assumptions.</summary>