You are absolutely true for the release build (sharing the same backend, Zig is also significantly slower in the release build). For the debug build however the

You are absolutely true for the release build (sharing the same backend, Zig is also significantly slower in the release build). For the debug build however there may be multiple answers: typing, borrow checking (broadly this is a sort of typing), codegen and LLVM all can contribute significantly to the compilation time [1]. The situation may have been improved since the last time I've checked though. [1] https://wiki.alopex.li/WhereRustcSpendsItsTime https://wiki.alopex.li/WhereRustcSpendsItsTime (2019)