⚠️ THIS POST IS GENERATED WITH LLMs: This post is newly generated a few times a week based on trending articles from hacker news. It takes the tone of my writing style, takes the topic from Hacker News - throws in some LLM magic and generates this post. Please be aware I don’t read what gets generated here - it means I may agree, I may not - its a crap shoot - its not meant to be an opinion piece but merely an experiment with the services from OpenRouter - last updated Sunday 28 December 2025
Why uv Flies While Pip Walks
Let’s talk about speed. Not the “oh, it’s a bit quicker” kind, but the leave-your-coffee-unfinished kind. You know that feeling when you’re waiting for a package install, mentally drafting your will? Yeah, uv fixes that. But here’s the thing – everyone credits Rust. And sure, Rust is great. But Rust alone doesn’t make a tool fast. It’s like crediting the oven for a perfect brisket. The real magic? Knowing what not to do.
Back in the day, Python packaging was like a Rube Goldberg machine. To install a package, pip had to run its setup.py script. But to run setup.py, it needed dependencies… which it could only discover by running setup.py. Classic catch-22. The result? Pip downloading half the internet, spawning subprocesses like it’s paying them commission, and occasionally faceplanting into missing build tools. It wasn’t pip’s fault – the ecosystem demanded chaos.
Then came the PEPs. Not the minty kind – the Python Enhancement Proposal kind. Starting around 2016, they quietly rewrote the rules:
- PEP 518 gave us
pyproject.toml, a place to declare build deps without code execution. (Thank you, Rust’s Cargo, for the TOML inspiration.) - PEP 517 split build frontends from backends, so pip didn’t need a PhD in setuptools.
- PEP 621 standardized dependency declarations – no more parsing Python to read metadata.
- PEP 658 (live in 2023) finally let resolvers fetch deps without downloading entire wheels.
By February 2024, when uv launched, the runway was paved. Python packaging had grown up.
But speed isn’t just about adding – it’s about cutting.
uv looks at pip’s baggage and says “nah.” No .egg support (obsolete for a decade). No pip.conf (goodbye, config file spaghetti). No compulsive bytecode compilation. No touching system Python without explicit permission. It enforces specs strictly, because bending backward for malformed packages means maintaining code paths nobody needs.
And here’s my favorite: uv ignores upper bounds in requires-python. Why? Because declaring python<4.0 is usually just superstition. Teams haven’t tested on Python 4, not because it’ll actually break. Dropping this cuts resolver backtracking like a hot knife through butter.
Some tricks aren’t even Rust-dependent.
Parallel downloads? Global caching via hardlinks? HTTP range requests to fetch metadata without downloading full wheels? That’s just good engineering – Python could’ve done it years ago. uv’s secret sauce isn’t the language; it’s the design. Prioritize fast paths, cache aggressively, and resolve before downloading.
Rust does help at the margins: zero-copy deserialization, thread-level parallelism without GIL drama, and packing versions into tiny u64 integers. But none of that matters if you’re still executing code to find dependencies.
Here’s the takeaway: Ecosystems move slow until they don’t. For years, Python packaging was held hostage by legacy choices – executing code to discover requirements, tolerating outdated formats, prioritizing compatibility over speed. uv works because it’s built for today’s standards, not yesterday’s compromises.
The lesson isn’t “rewrite everything in Rust.” It’s simpler: fast tools need fast ecosystems. Static metadata. No mandatory code execution. Resolve first, download later. Nail that, and speed follows – in any language.
Now, if you’ll excuse me, I’ve got packages to install. And thanks to uv, I might actually finish that coffee. ☕
