Good spotto! That's an old WASI runtime from wasmerjs (https://github.com/wasmerio/wasmer-js).

That's not the WASI runtime being used in this playground. The one in this playground is @runno/wasi-motor (https://github.com/taybenlor/runno/tree/main/packages/wasi-m...). I haven't released it as an NPM package, but it's all MIT so feel free to copy it.