Rust's channel is entirely lock-free. It always was, ever since the first 1.0 release.

This is why I think Rust project sometimes has misguided priority. Is making channel implementation lock-free a good use of pre-1.0 time? Evidently, as shown by Go, lock-free channel is not necessary for wide use, and can be added later. Implementation work should have been deprioritized and probably spent on, say, async IO like Tokio.