I've loved the ergonomics of using tarpc for Rust projects, but I wanted a higher performance RPC library that could take advantage of bitcode's serialization speed and size https://david.kolo.ski/rust_serialization_benchmark/, that didn't depend on Tokio.
The problem with Tokio is it still doesn't have proper support for io_uring, and maybe never will due to its work stealing runtime. As such, I implemented a transport using HTTP 3 on Compio, a thread per core async runtime with great io_uring performance, HTTP3 support.