We are more or less trying to solve this exact problem with Wasm Components [1]. If core WebAssembly is a portable instruction format, WebAssembly Components are a portable executable/linkable format.

Using them is unfortunately not yet quite as easy as using repr(wasm)/extern "wasm". But with wit-bindgen [2] and the wasm32-wasip2 target [3], it's not that hard either.

[1]: https://youtu.be/tAACYA1Mwv4

[2]: https://github.com/bytecodealliance/wit-bindgen

[3]: https://doc.rust-lang.org/nightly/rustc/platform-support/was...