alt Hacker NewsRust does have incremental rebuilds, yes.
Folks have worked tirelessly to improve the speed of the Rust compiler, and it's gotten significantly faster over time. However, there are also language-level reasons why it can take longer to compile than other languages, though the initial guess of "because of the safety checks" is not one of them, those are quite fast.
> How slow are we talking here?
It really depends on a large number of factors. I think saying "roughly like C++" isn't totally unfair, though again, it really depends.
My initial guess would be "because of the zero-cost abstractions", since I read "zero-cost" as "zero runtime cost" which implies shifting cost from runtime to compile time—as would happen with eg generics or any sort of global properties.
(Uh oh, there's an em-dash, I must be an AI. I don't think I am, but that's what an AI would think.)