UV also has the distinct advantage in dependency resolution that it didn't have to implement the backwards compatible stuff Pip does, I think Astral blogged on it. If I can find it, I'll edit the link in.
That said, your point is very much correct, if you watch or read the Jane Street tech talk Astral gave, you can see how they really leveraged Rust for performance like turning Python version identifiers into u64s.
Not OP, but one example where it is a bit harder to do something in Rust that in C, C++, Zig, etc. is mutability on disjoint slices of an array. Rust offers a few utilities, like chunks_by, split_at, etc. but for certain data structures and algorithms it can be a bit annoying.
It's also worth noting that unsafe Rust != C, and you are still battling these rules. With enough experience you gain an understanding of these patterns and it goes away, and you also have these realy solid tools like Miri for finding undefined behavior, but it can be a bit of a hastle.
That's a pretty big claim. I don't doubt that a lot of uv's benefits are algo. But everything? Considering that running non IO-bound native code should be an order of magnitude faster than python.
Its a pretty well-supported claim. uv skips doing a number of things that generate file I/O. File I/O is far more costly than the difference in raw computation. pip can't drop those for compatibility reasons.
I don't think the article you linked supports the claim that none of UV performance improvements are related to using rust over python at all. In fact it directly states the exact opposite. They have an entire section dedicated to why using Rust has direct performance advantages for UV.
> 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.
This is either an overly pedantic take or a disingenuous one. The very first line that the parent quoted is
> uv is fast because of what it doesn’t do, not because of what language it’s written in.
The fact that the language had a small effect ("a bit") does not invalidate the statement that algorithmic improvements are the reason for the relative speed. In fact, there's no reason to believe that rust without the algorithmic version would be notably faster at all. Sure, "all" is an exaggeration, but the point made still stands in the form that most readers would understand it: algorithmic improvements are the important difference between the systems.
Vague. What's pretty close? I mean, even for IO bound tasks you can pretty quickly validate that the performance between languages is not close at all - 10 to 100x difference.