Unity / C# bindings (oxbitnet-csharp)

[m96-chan]

Summary

Add C# bindings for oxbitnet, enabling Unity and .NET applications to run BitNet b1.58 inference with wgpu.

Approach

• C FFI crate (oxbitnet-ffi) wrapping the Rust oxbitnet crate (shared with Swift bindings)
• C# P/Invoke wrapper with managed API
• Unity-friendly: native plugin (.so/.dylib/.dll) + C# scripts
• Publish as NuGet package: OxBitNet
• Streaming token output via callback delegate or IAsyncEnumerable

API sketch

var model = await BitNet.Load("model.gguf");

var messages = new[] {
    new ChatMessage("system", "You are a helpful assistant."),
    new ChatMessage("user", "Hello!")
};

model.Chat(messages, token => Console.Write(token), new GenerateOptions {
    Temperature = 0.7f,
    MaxTokens = 256
});

model.Dispose();

Unity usage

public class BitNetChat : MonoBehaviour
{
    private BitNet model;

    async void Start()
    {
        model = await BitNet.Load("model.gguf");
    }

    public async void OnSend(string userMessage)
    {
        await model.Chat(
            new[] { new ChatMessage("user", userMessage) },
            token => chatUI.AppendText(token)
        );
    }
}

Tasks

• C FFI crate (oxbitnet-ffi) with stable ABI (shared with Swift bindings (oxbitnet-swift) #6)
• C# P/Invoke bindings + managed wrapper
• Unity native plugin setup (multi-platform .so/.dylib/.dll)
• Interactive chat example (.NET console)
• Unity sample scene
• NuGet publish in CI
• README with quick start (both .NET and Unity)