Rust's type system takes up a surprisingly small portion of compilation time. See the comment rooted at [0] for some discussion. tl;dr: Profiling and tests sho

Rust's type system takes up a surprisingly small portion of compilation time. See the comment rooted at [0] for some discussion. tl;dr: Profiling and tests show that codegen and LLVM work takes up the lion's share of compilation time. The borrow checker itself isn't that expensive in the grand scheme of things, and languages like OCaml show that it's very feasible to have a complex type system that compiles quickly. [0]: https://news.ycombinator.com/item?id=22935795 https://news.ycombinator.com/item?id=22935795