uv is fast because of what it doesn’t do, not because of what language it’s written in. The standards work of PEP 518, 517, 621, and 658 made fast package management possible. Dropping eggs, pip.conf, and permissive parsing made it achievable. Rust makes it a bit faster still.

pip could implement parallel downloads, global caching, and metadata-only resolution tomorrow. It doesn’t, largely because backwards compatibility with fifteen years of edge cases takes precedence. But it means pip will always be slower than a tool that starts fresh with modern assumptions.

Тимдебилдинг

When multiple tasks need the same resource, how do you ensure the work happens exactly once? uv’s solution is OnceMap - a lightweight concurrent memoization primitive that powers deduplication across the resolver and installer.