diff --git a/.github/workflows/build.cqrs_flow.dotnet.yml b/.github/workflows/build.cqrs_flow.dotnet.yml
index 39a32be..e4684dd 100644
--- a/.github/workflows/build.cqrs_flow.dotnet.yml
+++ b/.github/workflows/build.cqrs_flow.dotnet.yml
@@ -24,7 +24,7 @@ jobs:
             - name: Setup .NET Core
               uses: actions/setup-dotnet@v1
               with:
-                  dotnet-version: "5.0.100"
+                  dotnet-version: "5.0.x"
                   
             - name: Restore NuGet packages
               run: dotnet restore
diff --git a/CQRS_Flow/.NET/Core/Core.Testing/Core.Testing.csproj b/CQRS_Flow/.NET/Core/Core.Testing/Core.Testing.csproj
index d0e2685..919a15f 100644
--- a/CQRS_Flow/.NET/Core/Core.Testing/Core.Testing.csproj
+++ b/CQRS_Flow/.NET/Core/Core.Testing/Core.Testing.csproj
@@ -4,14 +4,14 @@
         <TargetFramework>net5.0</TargetFramework>
         <Nullable>enable</Nullable>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
+        <IsTestProject>false</IsTestProject>
     </PropertyGroup>
 
     <ItemGroup>
         <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="5.0.1" />
         <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="5.0.0" />
         <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="5.0.0" />
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
-        <PackageReference Include="Microsoft.DotNet.InternalAbstractions" Version="1.0.500-preview2-1-003177" />
+        <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
         <PackageReference Include="NSubstitute" Version="4.2.2" />
         <PackageReference Include="xunit" Version="2.4.1" />
         <PackageReference Include="Microsoft.AspNetCore.TestHost" Version="5.0.7" />
diff --git a/CQRS_Flow/.NET/Core/Core.Testing/SerializationExtensions.cs b/CQRS_Flow/.NET/Core/Core.Testing/SerializationExtensions.cs
index 32f93aa..429e593 100644
--- a/CQRS_Flow/.NET/Core/Core.Testing/SerializationExtensions.cs
+++ b/CQRS_Flow/.NET/Core/Core.Testing/SerializationExtensions.cs
@@ -14,7 +14,7 @@ public static class SerializationExtensions
         /// <returns>deserialized object</returns>
         public static T FromJson<T>(this string json)
         {
-            return JsonConvert.DeserializeObject<T>(json);
+            return JsonConvert.DeserializeObject<T>(json)!;
         }
 
         /// <summary>