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9th March 2026

Research Luau WebAssembly: Browser Playground + Python wasmtime — Luau WebAssembly explores compiling the Luau scripting language (used by Roblox) to WebAssembly for interactive browser environments and Python integration via wasmtime. By leveraging Emscripten, the project creates a streamlined WASM module that runs in the browser (with a playground and Pyodide integration) and server-side Python. Key technical adaptations include custom output capture, flexible WASM imports for wasmtime, and Python wrappers that handle C++ exception lifecycles.

Luau is an MIT licensed "small, fast, and embeddable programming language based on Lua with a gradual type system", created by Roblox.

As part of my ongoing obsession with sandboxed runtimes I decided to see if I could get it working via WebAssembly in both Python and Pyodide.

Posted 9th March 2026 at 9:46 pm

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