I've always felt that parts of the Rust standard library to be weirdly un-rusty. Like indexing a vector panicking instead of returning a Some(T) in case the index is out of bounds. It's easy to avoid if you put the effort in of course, but it did always feel weird that one of the first data structures you learn has this behavior right out of the gate.
I sure wish they'd rewrite the Azure Linux VM Agent in Rust. That thing normally burns 10-15% of a core, and also blocks VM restart for tens of minutes, god knows why.
I've seen certain MSFT engineers get a lock ordering warning from taking mutexes in a wrong order and "fix" it by using a spin loop + try lock instead.
reminds me of the tales from https://oxide.computer/blog/iddqd-unsafe