diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 4df9af2..3848ff8 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -4,6 +4,8 @@ Release notes
 ### Unreleased
 
 * Fixed subject name when using `_.Should()`
+* On .NET 8, `Map<_, _>` now serializes as an object (not array) for non-`string` key types (
+  using `WithMapFormat(MapFormat.Object)` in FSharp.SystemTextJson)
 
 ### 1.3.7 (2024-03-15)
 
diff --git a/src/Faqt/Faqt.fsproj b/src/Faqt/Faqt.fsproj
index cd6e9db..39e2a30 100644
--- a/src/Faqt/Faqt.fsproj
+++ b/src/Faqt/Faqt.fsproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net5.0;net7.0</TargetFrameworks>
+    <TargetFrameworks>net5.0;net7.0;net8.0</TargetFrameworks>
     <Version>1.3.7</Version>
     <Authors>Christer van der Meeren</Authors>
     <Description>A fluent assertion library for F#.</Description>