I previously worked at Bytedance and we've maintained a Rust zero-copy gRPC/Thrift implementation for 4 years: https://github.com/cloudwego/volo, it is based on Bytes crate (reference counting bytes, for folks don't familiar with Rust ecosystem). A fun fact: when we measuring on our product environment, zero-copy isn't means higher performance in lots of scenarios, there are some trade-offs:

1. zero-copy means bytes are always inlined in the raw message buffer, which means the app should always access bytes by a reference/pointer

2. You cannot compress the RPC message, if you want to fully leverage the advantages from zero serdes/copy

3. RC itself

Speaking of volo I'm trying to implement a etcd shim with SurrealKV. Haven't been able to get the OG etcd E2E conformance test 100% passed yet so I'm not releasing it just now

same thing with io_uring zero copy in my limited testing: buffer usage accounting is not free and copying memory makes things drastically simpler.