Language lanes
You write a toolkit in the language you already use. The runtime compiles it to WASM inside its own sandbox — the compiler is itself WASM, so there's no toolchain on your machine and untrusted source never touches a native compiler.
| lane | notes |
| JS | via Javy; the fastest lane to a first build |
| C | clang in-sandbox; full stdio |
| Go | via a yaegi interpreter; stdlib |
| Rust | mrustc → clang, full std; slower, cached |
| Zig | compute today (stdio commands are a known gap) |
For a self-authored command you point build-inline at a source file; for a
durable toolkit the manifest's #+BUILD_LANG and #+BUILD_SRC drive the build.
wb toolkit build-inline rev rust ./reverse.rs
Build + register + run in one step: Self-authoring & hot-swap