TL;DR: uv is an extremely fast Python package manager, written in Rust.
Obligatory “there are now 15 competing standards”
For real though, this looks interesting. I am a long time poetry user, I’ve been mostly happy with it but I do think it could stand to be a little faster. I’ll have to try this out sometime.
Poetry support is on their roadmap!
What’s that mean, like they aim to become a drop-in replacement for poetry too? Or make uv able to work with a poetry-style pyproject.toml? I couldn’t find any info about that.
Hmm, I just re-read the blog post and GitHub where I thought I read that and I think I was mistaken…
uv
is fantastic. I would highly recommend it. I’ve used it in a quite complex environment, with no issues (quite an achievement!) and it’s about 10x faster than pip.I mean… I guess it’s not surprising given
uv
is written in Rust and pip is written in Python, but even so given pip is surely IO bound I was expecting something like 4x improvement. 10x is impressive.Having used it for work, I really don’t understand the appeal, especially when compared to tools like Poetry. Uv persists in the dependency on requirements.txt, doesn’t streamline the publishing process, and contrary to the claims, it’s not a drop-in replacement for pip, as the command line API is different.
It’s really fast, which is nice if you’re working on a nightmare codebase with 3000 dependencies, but most of us aren’t, and Poetry is pretty damned fast.
If uv offered some of what Poetry does for me, if at the very least we could finally do away with requirements.txt and adopt something more useable – baked into pyproject.toml of course – then I’d be sold. But this is just faster pip.
Early on uv was only trying to replace pip. This latest update is a big step towards becoming a poetry (and pyenv/pipx) replacement too.
Now if they could just help defuckulate the Pypi search problem.
It’s written in Rust.
All jokes about the Rust Evangelism Strike Force aside, various parts of the industry are finally starting to think that “If it’s written in Rust, we have less to worry about with respect to that thing, so we won’t torture the devs and force them to sneak it in the side door anyway.”
It’s a thing that I’ve been seeing at work for the last few years.
uv 0.3 introduces a cross platform lock file: https://docs.astral.sh/uv/concepts/projects/#lockfile
More precise details on the compatibility of
uv pip
withpip
are documented here: https://docs.astral.sh/uv/pip/compatibility/Uv is currently only a pip replacement as a dependency resolver (and downloader), it was actually adopted by astral from a different dev afaik
Their vision is to evolve it into a “Cargo for Python”, so it’s coming.
uv is now capable of installing and managing Python itself, making it entirely self-bootstrapping:
Looking forward to this. One of the blind spots of poetry was to ignore the issue of managing python versions themselves. I’m happy to see they’re covering so many aspects of dependency management and replicability.
Is that a real problem? I’ve never considered that a python package manager should be or could be faster.
To be fair, I don’t use python professionally.
definitely not the real reason for a project like this to exist. Python package management can be nightmarish at times depending on what you’re doing. between barebones
requirements.txt
, Poetry, and the differentconda
s there’s a ton of fragmentation, and none of them do everything you’d want in an ideal way. above and beyond speed, i thinkuv
is another attempt at it. but it could just be another classic xkcd moment where now there’s just another standard to deal withuv
is a drop-in replacement forpip
. There’s no extra standard. It’s pareto better. Honestly the Python community would do the world a favour if the deprecated pip and adopted uv as the official tool, but you can guess how likely that is…as you might have guessed i haven’t really tried it, but i have been reading about it. that said i have used “drop in replacement” tools like this (we use
pnpm
at work), and a drop in replacement is not without quirks. they wouldn’t have made a different tool altogether if it was really a 1:1 replacement. just because the commands are the same doesn’t mean it behaves the same. i.e. i doubt one person on the team could be usinguv
while everyone else sticks topip
they wouldn’t have made a different tool altogether if it was really a 1:1 replacement
Why not? It’s 10x faster.
I think it might have some other new features but you don’t need to use those.
i doubt one person on the team could be using uv while everyone else sticks to pip
This is exactly what we do at work. There’s no way I could convince everyone to switch to
uv
so I just switch between them based on an environment variable.It even supports random stuff like
pip install --config-settings editable_mode=compat --editable foo
which is required for static tooling to work (e.g. Pyright).
Yes. For the project I work on
pip install
takes about 60 seconds and replacing it withuv
reduces that to about 7 seconds. That’s a very significant improvement. Much less annoying interactively and in CI we do this multiple times so it saves a significant chunk of time.Just out of curiosity, how often do you have to run
pip install
?I dunno maybe once a week or so? We don’t actually have a system that detects if your
pip install
is out of sync withpyproject.toml
yet so I run it occasionally just to make sure.And it runs in CI around a dozen times for each PR. Yeah not ideal but there are goodish reasons which I can explain if you want.
No, that makes perfect sense. Thank you for explaining.
I like hearing about other people’s environments, because it gives perspective.
The performance is just a “nice to have”.
Python package management, especially at scale is infuriating. At work we use python microservices in docker containers and it infuriates me trying to update the one our team is responsible for.
I always like to rant that python 3rd party package management tools are a mistake. We should’ve gone for an “as simple as possible” setup instead of all this.
So I’m sceptical of UV on principle since it’s yet another 3rd party package manager but if it can do all of this and not be a nightmare I’ll be ok with it.
I think the main focus is around building out the tool chain - I would think being fast is just a side benefit and the main benefit is being written as the same language as what they want to use for the rest of “cargo”
This is incredible. Truly hats off to the folks at Astral. Can’t wait to try all this out and replace all our old bespoke tooling.
Isn’t
uv
being used as a package manager/resolver inrye
? I’m usingrye
for my new projects and it’s nice becauseruff
andpytest
are being unified in it too.Yeah it is, eventually they want UV to have feature parity with rye and rye will basically just be a pointer to UV
Rye’s developer on their plans for Rye in the context of uv’s latest release:
Very impressive results. I think I’ll give the tool a try next time we’re working on a small project. I’m dissatisfied with the existing packaging solutions.
Looks nice. The edge cases will be what determines if it gains adoption
This is great!
@burntsushi@programming.dev, do you know is Astral is working with prefix.dev and their Pixi project? They seem to now have overlapping concerns.
I don’t think they have anything to do with each other, it looks like prefix.dev uses conda packages.
Conda is their primary focus, but they support well more than conda packages.