It is a great deal more flexible having concurrency constructs built as library features as opposed to baked into the language. If the constructs provided don't

It is a great deal more flexible having concurrency constructs built as library features as opposed to baked into the language. If the constructs provided don't make the same performance tradeoffs that your use case demands, you can build your own. These can provide safe, statically verified APIs by leveraging Rust's ownership and lifetime semantics. Unfortunately channel selection and futures are still pretty raw at the moment (it remains to be seen if it will be ready for 1.0), but other constructs such as threads, channels and mutexes are looking pretty strong for 1.0.