Feather strips all references to FSharp.Core from any .NET assembly, by either removing useless attributes and methods or by replacing them with built-in equivalents.

Feather works fully at compile-time (using Fody), and thus does not require any runtime dependency.

Therefore, Feather can be used to code in F#, while having outputs assembly that do not require any extra dependencies, and can thus be used directly within C# projects without requiring FSharp.Core.

It is currently a work in progress. Right now, all references to FSharp.Core are merely removed; no equivalent function calls are used.

The NuGet package has not been published yet. However, as soon as it will be online, the following will apply to the installation process of Feather.

Add a dependency to your project:

<ItemGroup>
  <PackageReference Include="Feather.Fody" Version="0.1.0" />
</ItemGroup>

Then, install the Feather weaver by creating a FodyWeavers.xml file and setting its content to:

<?xml version="1.0" encoding="utf-8" ?>
<Weavers>
  <Feather /> 
</Weavers>

See the implementation issue for progress details.

A test assembly is available in the Feather.TestAssembly directory, and contains many declarations that make use of F#-specific features.

This assembly is modified by Feather.Fody on compilation, and should then lose all its references to FSharp.Core.

The Feather.Tests projects finally ensures that both these statements are true:

• Feather.TestAssembly.dll does not contain any reference to FSharp.Core.
• Feather.TestAssembly.dll can be loaded, and works flawlessly.

1. Add test cases to Feather.TestAssembly.
2. Make sure they work after removal of all F# references in Feather.Tests.

1. Grab dnSpy to analyze output assemblies.
2. Find a common pattern or specific use.
3. Implement a replacement in ModuleWeaver.cs.