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`builtins.wasm` is now a (experimental) thing in @determinate.systems’ nix, with a PR open for upstream nix. This lets you extend the nix language by compiling C/C++/Rust/etc into safely sandboxed, platform-independent plugins! determinate.systems/blog/builtin...

determinate.systemsA new chapter for the Nix language, courtesy of WebAssemblyDeterminate Nix now supports Wasm functions in Nix expressions, bringing a range of new possibilities to the Nix ecosystem

5/3/26, 7:44 pm0 reposts5 likes

so excited for this

This became real a lot quicker than I thought 😂 There's also a talk about this tomorrow at PlanetNix! bsky.app/profile/surm...

Surma@surma.dev

Nix friends: How terrible is this idea? I added `builtins.runWasm` to nix, allowing you to call out to Wasm. The Wasm is reset every time, so the functions remain pure. This gives you a (performant?) escape hatch for things that Nix is missing. E.g parsing YAML (here: via Rust)