(wazero maintainer) we have a popular allocation example, which shows how GC ends up embedded (really malloc/free) in wasm produced by Rust or TinyGo. You are right that whatever produces wasm, if needs to allocate memory, is doing that by embedding some implementation into the wasm (during compilation).

[1] https://github.com/tetratelabs/wazero/tree/main/examples/all...