Did you forget to tell Claude to make it run fast?

(I am not joking. I did a port of an old utility, Dos Navigator, and I gave Claude+Codex a set of KPIs: cold start under 100ms, 30MB RAW image preview under 50ms, and a few others. I went to bed, and I woke up to a file manager written in Swift that is a joy to use, its so fast, esp. when previewing images. If I haven't requested it, it would likely be way slower).