* Sum types, and with them, exhaustive match checks

* Immutability by default, including a warning for unnecessary mutability

* Usable documentation even when the library author wrote none

* Extremely low-friction testing, including fuzzing

To name a few.

Racing to get an HTTP service that starts but doesn't do anything you want it to do correctly isn't really useful; in my experience, that's the only advantage e.g. Python, Go, etc really give you over Rust.