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uv downloads overtake Poetry for Wagtail users

heisig

I recently switched to uv, and I cannot praise it enough. With uv, the Python ecosystem finally feels mature and polished rather than like a collection of brittle hacks.

Kudos to the uv developers for creating such an amazing piece of software!

matsemann

Yeah, switched to writing python professionally ~4 years ago, and been low key hating the ecosystem. From a java and javascript background, it's mostly been npm/mvn install and it "just works". With python, there's always someone being onboarded that can't get it to work. So many small issues. Have to have the correct version per project, then have to get the venv running. And then installing it needs to build stuff because there's no wheel, so need to set up a complete c++ and rust toolchain etc., just to pull a small project and run it.

uv doesn't solve all this, but it's reduced the amount of ways things can go wrong by a lot. And it being fast means that the feedback-loop is much quicker.

notpushkin

Python has been mostly working okay for me since I switched to Poetry. (“Mostly” because I think I’ve run into some weird issue once but I’ve tried to recall what it was and I just can’t.)

uv felt a bit immature at the time, but sounds like it’s way better now. I really want to try it out... but Poetry just works, so I don’t really have an incentive to switch just yet. (Though I’ve switched from FlakeHeaven or something to Ruff and the difference was heaven and hell! Pun in’tended.)

gunalx

I cannot share the same experiences. mvn is a buggy mess, randomly forgetting dependencies, and constantly needing a full clean to not die on itself. npm and the entire js ecosystem feels so immature with constant breaking changes, and circular dependency hell, when trying to uppgrade stuff.

Etheryte

That's an issue with the packages themselves though, not with package management as a whole. You and the comment above you are talking about different things. While there's plenty of pain to be had with npm, if you have a project that used to work years ago, you can generally just clone, install and be done, even if on older versions. On Python this used to mean a lot of hurt, often even if it was a fresh project that you just wanted to share with a colleague.

amelius

But how does it work with components that require libraries written in C?

And what if there are no binaries yet for my architecture, will it compile them, including all the dependencies written in C?

matrss

IMO if you require libraries in other languages then a pure python package manager like uv, pip, poetry, whatever, is simply the wrong tool for the job. There is _some_ support for this through wheels, and I'd expect uv to support them just as much as pip does, but they feel like a hack to me.

Instead there is pixi, which is similar in concept to uv but for the conda-forge packaging ecosystem. Nix and guix are also language-agnostic package managers that can do the job.

amelius

But for example, if I install the Python package "shapely", it will need a C package named GEOS as a shared library. How do I ensure that the version of GEOS on my system is the one shapely wants? By trial and error? And how does that work with environments, where I have different versions of packages in different places? It sounds a bit messy to me, compared to a solution where everything is managed by a single package manager.

dagw

UV is not (yet) a build system and does not get involved with compiling code. But easily lets you plug in any build system you want. So it will let you keep using whatever system you are currently using for building your C libraries. For example I use scikit-build-core for building all of my libraries C and C++ components with cmake and it works fine with uv.

datadeft

    uv build
    Building source distribution...
    running egg_info
    writing venv.egg-info/PKG-INFO
    Successfully built dist/venv-0.1.0.tar.gz
    Successfully built dist/venv-0.1.0-py3-none-any.whl

Wulfheart

Ok, you convinced me to give it a try. Tbh, I am a casual user of python and I don't want to touch it unless I have a damn good reason to use it.

mlnj

You do not need a damn good reason for this. Just try it out on a simple hello world. Then try it out on a project already using poetry for eg.

uv init

uv sync

and you're done

I'd say if you do not run into the pitfalls of a large python codebase with hundreds of dependencies, you'll not get the bigger argument people are talking about.

stavros

I don't think you need to sync, do you? It always just does it when running.

That said, I do wish uv had `uv activate`. I like just working in the virtualenv without having to `uv run` everything.

freeamz

the_mitsuhiko

Unlike uv this tool is unlikely to solve problems for the average Python user and most likely will create new ones.

freeamz

Agree, however for user who want to get faster speed out of python wouldn't that just work with rustpython? It can also run in the browser then.

qwertox

I've read so much positive feedback about uv, that I'd really like to use it, but I'm unsure if it fits my needs.

I was heavily invested into virtualenv until I had to upgrade OS versions, which upgraded the Python versions and therefore broke the venvs.

I tried to solve this by using pyenv, but the need of recompiling Python on every patch wasn't something which I would accept, specially in regards to boards like Raspberry Pis.

Then I tried miniconda which I initially only liked because of the precompiled Python binaries, and ultimately ended up using pyenv-managed miniforge so that I could run multiple "instances" of miniforge and therefore upgrade miniforge gradually.

Pyenv also has a plugin which allows to set suffixes to environments, which allows me to have multiple miniforges of the same version in different locations, like miniforge-home and miniforge-media, where -home has all files in the home dir and -media has all files on a mounted nvme, which then is where I put projects with huge dependencies like CUDA inside, not cluttering home, which is contained in a VM image.

It works really great, Jupyter and vscode can use them as kernels/interpreters, and it is fully independent of the OS's Python, so that OS upgrades (22.04 -> 24.04) are no longer an issue.

But I'm reading about all these benefits of uv and wish I could use it, but somehow my setup seems to have tied my hands. I think I can't use uv in my projects.

Any recommendations?

Edit: Many of my projects share the same environment, this is absolutely normal for me. I only create a new environment if I know that it will be so complex that it might break things in existing environments.

the_mitsuhiko

I’m a bit confused why uv is not an option for you. You don’t need to compile Python, it manages virtualenvs for you, you can use them with Jupyter and vscode. What are you missing?

qwertox

So the only difference is that Conda also isolates "system" libraries (like libcublasLt.so), or does uv also do this?

It's not that uv is not an option for me, I made this move to miniforge before uv was on my radar because it wasn't popular, but I'm still at a point where I'm not sure if uv can do what I need.

rmholt

According to these docs

https://docs.astral.sh/uv/pip/environments/

I think uv supports conda envs

the_mitsuhiko

uv does not ship system libraries because pypi does not have them. There is a philosophical difference between pypi and conda today. I believe over time pypi will likely ship some system libraries but we will see.

datadeft

I have moved to uv few months back and never looked back. I use it with venv and it works very well. There is a new environment handling way with uv:

- uv init new-py-env

- cd new-py-env

- uv add jupyter

- uv build

These are executed super fast. Not sure if this could help your situation but it is worth to be aware of these.

secondcoming

The python ecosystem has become a disaster. Even reading your post gave me a headache.

mihaic

I keep reading praise about uv, and every single time I never really understand what the problems are that it addresses.

I've got a couple quite big Django projects for which I've used venv for years, and not once have I had any significant issues with it. Speed at times could have been better and I would have liked to have a full dependency list lock file, but that never caused me issues.

The only thing that comes to mind is those random fails to build of C/C++ dependencies. Does uv address this? I've always seen people rave about other benefits.

hansihe

What makes it so great for me is the effortlessness.

I often use Python for quick one off scripts. With UV I can just do `uv init`, `uv add` to add dependencies, and `uv run` whatever script I am working on. I am up and running in under a minute. I also feel confident that the setup isn't going to randomly break in a few weeks.

With most other solutions I have tried in the Python ecosystem, it always seemed significantly more brittle. It felt more like a collection of hacks than anything else.

aneidon

You can even inline the dependencies:

https://docs.astral.sh/uv/guides/scripts/#declaring-script-d...

That plus this: https://news.ycombinator.com/item?id=42855258

Makes it pretty seamless for one-off scripts.

IshKebab

Not a surprise. I said it before and I'll say it again, all the competing projects should just shut up shop for the good of Python. uv is so much better it's like pushing penny farthings after the safety bike has been invented.

nikisweeting

That's rough for all the creators of poetry, pdm, pipenv, etc. to hear. They put in a ton of great work over the last decade, but I fear you may be right.

alwyn

I quite really like pdm! I can see why maybe poetry but especially pipenv might be replaced with uv, but what's the value of uv over pdm beyond performance? It ticks all my boxes otherwise.

ZuLuuuuuu

I am feeling the same way about PDM, it works very well, easy to configure and checks all the boxes feature-wise.

francasso

Beyond performance? Performance!

DHolzer

I recently checked out UV, and it's impressively fast. However, one challenge that keeps coming up is handling anything related to CUDA and Torch.

Last week, I started developing directly in PyTorch containers using just pip and Docker. With GPU forwarding on Windows no longer being such a hassle, I'm really enjoying the setup. Still, I can’t shake the feeling that I might be overlooking something critical.

I’d love to hear what the HN crowd thinks about this type of env.

jerrygenser

I've used uv with pytorch and cuda fine. What problem have you had?

I also use it in docker to build the container.

ZuLuuuuuu

PyCharm also added uv support in their latest versions.

We recently switched to PDM in our company because it worked very well in our tests with different package/dependency managers. Now I am rethinking if we should switch to uv while PDM usage is still not very wide-spread in our company. But PDM works very well, so I am not sure whether to keep using it.

ThibWeb

With the caveat I only have the package installers usage data for Wagtail downloads – pdm usage has fallen off a cliff, from 0.2% of downloads in January 2024, to 0.01% in January 2025. Roughly matches the uptake of uv.

Doesn’t make pdm bad in itself but that means there’ll be fewer pdm users around to report bugs, potentially fewer contributors to it too, fewer resources, etc.

ZuLuuuuuu

Indeed, on one hand PDM works great, but on the other hand we wouldn't want to choose a package manager which might not be maintained anymore after a few years because there are just not many users of it.

TOMDM

For the uninitiated what is the benefit of UV over pip?

I've been working with pip for so long now that I barely notice it unless something goes very wrong.

NeutralForest

- uv is aware of your dependencies, you can add/remove development dependencies, create group of development dependencies (test, lint, dev, etc) and add or remove those and only those at will. You can add dependencies and optional dependencies for a project as well, think my_app[cli,standard]. You don't need to have different requirements.txt for each case nor do you need to remove things by hand as you'd do in pip, since it doesn't remove deps when you remove a package for example. As a result, you can remove {conda,poetry,...} from your workflows.

- uv can install python and a virtualenv for you. Any command you run with `uv run` from the root of a repo will be aware of its environment, you don't even need to activate a virtualenv anymore. This replaces {pyenv, pyenv-virtualenv, virtualenvwrapper,...}.

- uv follows the PEPs for project config (dependencies, optional dependencies, tool configs) in the pyproject.toml so in case uv dies, it's possible to migrate away for the features are defined in the PEPs. Which is not the case for say, poetry.

- uv has a lock file and it's possible to make deps platform specific (Windows, Linux, MacOS, etc). This is in compliance with a PEP but not supported by all tools.

- uv supports custom indexes for packages so you can prefer a certain index, for example your company package index or pytorch's own index (for ML work).

- very fast, makes local dev very seamless and is really helpful in CI/CD where you might just setup and tear down python envs a lot.

Also, the team is responsive on Github so it's easy to get help.

adrian17

Does this also replace, or work well with tox? We currently use it to run basic CI/local workflows (`tox -e lint` for all linters, `tox -e py310`, `tox -e py312` to run tests suites on chosen interpreters' environments), and to set up a local environment with package installed in-place (so that we can run `myprogram -arg1 -arg2` as if it was installed via `pip`, but still have it be editable by directly editing the repo).

With how much the ecosystem is moving, I don't know whether the way we're doing it is unusual (Django and some other big projects still have a tox.ini), obsolete (I can't find how ux obsoletes this), or perfectly fine and I just can't find how to replace pip with ux for this use case.

NeutralForest

I'm not personally releasing a ton of internal packages where I work but I know of https://github.com/tox-dev/tox-uv. Haven't tried it yet though but it seems to do what you want. I also saw that nox (tox but in python instead of a tox.ini file https://nox.thea.codes/en/stable/config.html), is supporting uv from what I understand.

I don't think there's a definite answer yet.

rschiavone

Not only it's faster, it also provides a lock file, `uvx tool_name` just like `npx`, and a comprehensive set of tools to manage your Python version, your venv and your project.

You don't need `pyenv`, `poetry` and `pipx` anymore, `uv` does all of that for you.

shellac

> over pip

It's a much more complete tool than pip. If you've used poetry, or (in other languages) cargo, bundler, maven, then it's like that (and faster than poetry).

If you haven't, in addition to installing dependencies it will manage and lock their versions (no requirements.txt, and much more robust), look after the environment (no venv step), hold your hand creating projects, and probably other things.

Edit to add: the one thing it won't do is replace conda et al, nor is it intended to.

montebicyclelo

It brings way more to the table than just being fast, like people are commenting. E.g. it manages Python for your projects, so if you say you want Python 3.12 in your project, and then you do 'uv run python my script.py', it will fetch and run the version of Python you specified, which pip can't do. It also creates lock files, so you know the exact set of Python package dependencies that worked, while you specify them more loosely. Plus a bunch of other stuff..

BiteCode_dev

The whole explaination is here: https://www.bitecode.dev/p/a-year-of-uv-pros-cons-and-should

The td;rd is that is has a lot less modes of failure.

jonatron

Faster.

maratc

Ok, and what's the advantage for the people who don't have "my pip is too slow" problem?

nicolasp

Wait times are in the order of tens of milliseconds instead of seconds. That makes a massive difference in how nice uv is to use vs pip.

prashnts

I can't stress how fast it is when using on resource constrained envs like a Pi Zero.

I intend to use system python there but previously poetry will simply crash the whole Pi while installing itself.

globular-toast

The only advantage over pip is it's faster. But the downside is it's not written in Python.

The real point of uv is to be more than pip, though. It can manage projects, so basically CLI commands to edit your `pyproject.toml`, update a lockfile, and your venv all in one go. Unlike earlier tools it implements a pretty natural workflow on top of existing standards where possible, but for some things there are no standards, the most obvious being lockfiles. Earlier tools used "requirements.txt" for this which was quite lacking. uv's lockfile is cross-platform, although, admittedly does produce noisier diffs than requirements.txt, which is a shame.

atoav

The problems start as soon as your scripts should run on more than your own computer.

If you pip install something, you install it on the system python (the python binary located at sys.executable). This can break systems if the wrong combination of dependencies comes together. This is why you should never install things via pip for other people, unless you asked them first.

Now how else would you install them? There is a thing called virtual environments, which basically allows you to install pip dependencies in such way, they are only there within the context of the virtual environment. This is what you should do when you distribute python programs.

Now the problem is how do you ensure that this install to the virtual environment uses specific versions? What happens when one library depends on package A with version 1.0 and another library depends on a package with version 2.0? Now what happens if you deploy that to an old debian with an older python version.. Before uv I had to spend literal days to resolve such conflicts.

uv solves most of these problems in one unified place, is extremely performant, just works and when it does not, it tells you precisely why.

bsdz

I feel for me, at least one nice thing about poetry over uv is, that if I have an issue or feature extension, I can just write my own plugin in pure Python. With uv, I'd need to learn Rust in addition to python/c/c++/etc.

I wonder what it would take to get poetry on par with uv for those who are already switching to it? Poetry is definitely very slow downloading multiple versions of packages to determine dependencies (not sure how uv works around this?). Does uv have a better dependency checker algorithm?

rmholt

For me personally the killer uv feature is pyenv integration, which poetry doesn't do

wiseowise

> I wonder what it would take to get poetry on par with uv

Different laws of physics, to start with.

brokegrammer

I switched from Poetry to uv last year. I like the speed and how it stores virtual envs in a .venv directory along with the project by default, whereas Poetry store it in a separate directory in your home directory by default, which makes it hard to work with tools that only discover virtual envs in the project root.

uv tool is also a great replacement for pipx.

I think it's the way to go for Python dependency management in 2025.

emblaegh

Man, I’m so jealous of insane praise that uv (and most other astral tools) gets. I don’t think ever seen anything so unanimously lauded around here.

mvATM99

With good reason honestly. They take all the best practices from existing tooling we had, discard the bad, and make it run blazingly fast.

Ruff for me meant i could turn 4 pre-commit hooks (which you have to configure to be compatible with each other too) into just 1, and i no longer dread the "run Pylint and take a coffee break" moment.

I jumped ship to UV recently. Though i was skeptical at first i don't regret it. It makes dependency management less of a chore, and just something i can quickly do now. Switching from Poetry was easy for me too, only package i had issues with was pytorch, but that just required some different toml syntax.

SilverSlash

Guess people here don't talk much about cargo. I wouldn't be surprised to learn that cargo inspired uv. Rust with cargo showed for the first time that tooling _can_ be good, even for systems programming languages.

BiteCode_dev

uv has been introduced as cargo for python: https://astral.sh/blog/uv-unified-python-packaging

weberer

Like with any social media site, you also have to consider the possibility that not all comments are 100% organic.

emblaegh

I’ve seen fishy looking engagement in hn before, but I’m inclined to think uv’s praise is genuine. It reflects the collective relief of seeing an extremely long and painful journey finally come to an end (hopefully).

orthoxerox

Tailscale?

emblaegh

It’s not really on my radar, but I’d be curious to know what other pieces of software get similar respect from their communities.

Euphorbium

Uv should replace pip for all I care.

ThibWeb

Well, seems like 100% what’s going to happen (for the majority of Wagtail users at least) if the current trend continues. I’m not sure if that’s a good thing to be frank. But we’ll have to adjust regardless.

darkfloo

As a semi casual user of python that had to battle w/ dependency management recently, can you elaborate on why that would not be a good thing ? I thought about switching our project to uv but could not find the time necessary

ThibWeb

Sure – and I think it’s certainly proving to be a good thing so far! My concerns are more longer-term. I see two primarily:

(1) As uv’s governance is driven by a for-profit company, I see incentives that will eventually compromise on its benefits.

(2) Python packaging has historically been very fragmented, and more recently there’s been lots of work on standardization. That work will be impacted when users massively shift to one package installer.

Neither of those things are clear negatives, but they’re worth being aware of.

jonatron

You may be overestimating the amount of time it takes to switch to uv.

freeamz

cibyr

What about it? RustPython is an alternative interpreter; it's not in the same category of thing as pip or uv.

zoobab

Plenty of packages still fail trying to spawn cmake, gcc and al.

UV does not solve all the hard problems.

Maybe switch to Pixi?

quleap

I'm extremely satisfied with Pixi. It fixes almost all the issues I had with conda and mamba. It supports both conda and pypi (via uv) packages. I don't know if uv fixes pip's dependency management hell. I settled on conda packages because pip was such a mess.

Vaslo

Switch to who?

KingMob

Google's not that broken yet: https://pixi.sh/latest/