It's very slow for the initial revision, as it has to compile all its dependencies. From there, if you add in full async/await support with a web server framework, you're looking at ~6sec iteration time. If you bring in LLVM's LLD instead of GNU or MSVC, you can bring that down to ~3-4sec. They're working on adding support for their own LLVM competitor, Cranelift, that should further reduce those times. It's only intended for debug/development builds, though, so you'll still need longer compile times for release.