I personally find the mention of the implementation language as part of a project description to be slightly interesting/informative, or at worst benign. Unlike the inevitable comments complaining about it.
Mercurial, written in Python, definitely experienced performance problems. Hilariously, the first search result I found when searching for "mercurial performance python" is https://wiki.mercurial-scm.org/OxidationPlan, which discusses reimplementing parts of Mercurial in — you guessed it — Rust.
Mercurial, written in Python, definitely experienced performance problems. Hilariously, the first search result I found when searching for "mercurial performance python" is https://wiki.mercurial-scm.org/OxidationPlan, which discusses reimplementing parts of Mercurial in — you guessed it — Rust.