diff --git a/src/Morphir.IR/Morphir.IR.fsproj b/src/Morphir.IR/Morphir.IR.fsproj
index 76c595fd..80c8738e 100644
--- a/src/Morphir.IR/Morphir.IR.fsproj
+++ b/src/Morphir.IR/Morphir.IR.fsproj
@@ -1,5 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
-  <PropertyGroup>
+  <PropertyGroup Condition=" '$(OS)' != 'Windows_NT' ">
+    <TargetFramework>netstandard2.1</TargetFramework>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(OS)' == 'Windows_NT' "> 
     <TargetFrameworks>netstandard2.1;net461</TargetFrameworks>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)'=='Release'">
diff --git a/src/Morphir.SDK.Testing/Morphir.SDK.Testing.fsproj b/src/Morphir.SDK.Testing/Morphir.SDK.Testing.fsproj
index fddc6c7c..3e75c2f6 100644
--- a/src/Morphir.SDK.Testing/Morphir.SDK.Testing.fsproj
+++ b/src/Morphir.SDK.Testing/Morphir.SDK.Testing.fsproj
@@ -1,9 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
+    <PropertyGroup Condition=" '$(OS)' != 'Windows_NT' ">
+        <TargetFramework>netstandard2.1</TargetFramework>
+    </PropertyGroup>
+    <PropertyGroup Condition=" '$(OS)' == 'Windows_NT' "> 
         <TargetFrameworks>netstandard2.1;net461</TargetFrameworks>
     </PropertyGroup>
-
+     
     <ItemGroup>
         <Compile Include="Testing.fs" />
         <Content Include="paket.references" />