Writing Node.js addons with .NET Native AOT

The C# Dev Kit team replaced C++ Node.js addons (built with node-gyp and requiring Python) with C# using .NET Native AOT. The post walks through building a Node.js native addon in C# using N-API, covering the project setup, module entry point with [UnmanagedCallersOnly], P/Invoke via [LibraryImport] with a custom DLL resolver pointing to the host process, UTF-8 string marshalling using Span<T> and ArrayPool, and exposing functions to TypeScript. The result eliminated the Python dependency, simplified CI pipelines, and matched C++ performance while opening the door to hosting .NET logic in-process within Node.js.