Charlie Marsh: uv: An Extremely Fast Python Package Manager

I recently watched a talk by the author of uv that was surprisingly fascinating 1. He goes into a few of the more notable hacks that they had to come up with to make it as fast as it is. The most interesting thing for me was that package resolution in python given constraints defined (eg. in requirements.txt) maps to a boolean satisfiability problem which is NP-complete. So uv uses a custom SAT solver to do this. I totally under-appreciated how much goes into this software and I'm bummed I have to use Poetry at work after having watched this talk. 1 link to this video edit: NP-complete not NP-hard

There is a talk about it from one of the authors here: link to this video tl;dw Rust, a fast SAT solver, micro-optimisation of key components, caching, and hardlinks/CoW.

…le things contributed into making uv faster, but listing a few dozens of them (surely a non-exhaustive lists) doesn't really enable you to make any conclusions about the relative importance of different improvements whatsoever. I suppose the mentioned talk0 (even though it's more than a year old now) would serve as a better technical report. 0 link to this video…

So much love for @burntsushi He's improved my life in so many ways, rg, ... and now also in Python with uv! Glad to see Charlie giving him the credit for figuring out the version comparison optimization in uv in 1. Also huge thank you to the whole Astral team for all they're doing on uv It's magic! 1: link to this video