IIUC, for typical programs, most of Rust compilation time is spent waiting for LLVM to spit out results. There's a plan to use https://github.com/CraneStation/

IIUC, for typical programs, most of Rust compilation time is spent waiting for LLVM to spit out results. There's a plan to use https://github.com/CraneStation/cranelift https://github.com/CraneStation/cranelift for debug builds instead of LLVM, which would make them faster at the cost of supporting fewer targets, and producing worse code.