> zero-cost multi-threading I think you mean zero cost abstractions. Which aren't usually zero cost, but just zero additional cost over doing it yourself. The

> zero-cost multi-threading I think you mean zero cost abstractions. Which aren't usually zero cost, but just zero additional cost over doing it yourself. There's no such thing as zero cost multi threading. Just tradeoffs. Rust actually doesn't help with performance here (it gets in the way often) but it definitely does help with correctness - which is truly hard with multi threaded programs.