Wasmtime/Wasmer are both written in Rust so it was easy to integrate them. By the way, Wasm3 is an interpreter, not a JIT compiler, but this also has some use cases! For example, running an instance from “cold storage” requires a JIT compilation step which might take more time then just interpreting it. It would be cool to have a fast interpret like Wasm3 too.

We’ve created a crate “uptown_funk” which enables us to write Rust code which easily integrates with both Wasmer and Wasmtime. It was very helpful in implementing WASI and it takes a little bit different approach than Wasmer and Wasmtime. Regarding, Wasmer vs. Wasmtime, we don’t have a preference yet, both are great!