I still don't get it, uv is checking if dependencies exist on disk, if they do it creates a link from the cache to your environment, it's a stat syscall and a hardlink syscall in the best of worlds (after solving dependency versions but that should already be done in a lockfile).

Interpreter startup time is hardly significant once in one invocation to set up your environment.

What makes Rust faster for downloading and unpacking dependencies. Considering how slow pip is and how fast uv is (100s of X) it seems naive to attribute it to the language.