[JTenerife]

"Therefore, rather than making you spend lots of time trying to reproduce the exact circumstances under which a runtime concurrency bug occurs, incorrect code will refuse to compile and present an error explaining the problem. As a result, you can fix your code while you’re working on it rather than potentially after it has been shipped to production. We’ve nicknamed this aspect of Rust fearless concurrency. Fearless concurrency allows you to write code that is free of subtle bugs and is easy to refactor without introducing new bugs."

https://doc.rust-lang.org/1.30.0/book/second-edition/ch16-00...

These sound like quite bold claims to me.

[remram]

Previous sentence in this paragraph:

> By leveraging ownership and type checking, __many__ concurrency errors are compile-time errors in Rust rather than runtime errors.

[mratsim]

I'm pretty sure the OP meant that concurrency introduces many subtle bugs that are not related to memory safety and so cannot be prevented by the Rust compiler hence fearless is a bold claim.