GitHub - Millillion/lasm: Lean for JavaScript and WebAssembly runtimes

Lean 4 for the JavaScript and WebAssembly world.

Lasm compiles ordinary Lean 4 programs ahead of time to WebAssembly. One Lean code base can become a Node server, a serverless or edge function, a WASI/Fastly module or a browser app. Because it is Lean, you can prove properties of the code you deploy. The flagship example, Conduit, is the RealWorld app with 117 proved theorems. Lasm ships on npm and brings Lean, Lake and its build tools with it; you only need Node (or Bun or Deno). npm create @lasm@latest my-app -- --template hono # then: cd my-app && npm install && npm run dev AI agents: this README is complete on its own. llms.txt is the short index, and docs/AI.md lists the rules that save you from wrong turns.

If Lasm is useful to you, I'd appreciate your sponsorship (more below).