Sometime after Minix 3 but before it had attained the critical mass for a self-sustaining community, compilation times went from 10 minutes on low-end hardware

Sometime after Minix 3 but before it had attained the critical mass for a self-sustaining community, compilation times went from 10 minutes on low-end hardware to ~3 hours, and the answer to the question "Why?" was "LLVM/clang".