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Uv is the best thing to happen to the Python ecosystem in a decade

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Re: Uv is the best thing to happen to the Python ecosystem in a decade

#471

Post by bastawhiz »

WatchDog wrote: post #421
anp wrote: post #205

Earlier quoted context omitted.

Might be worth noting that npm didn’t have lock files for quite a long time, which is the era during which I formed my mental model of npm hell. The popularity of yarn (again importing bundled/cargo-isms) seems like maybe the main reason npm isn’t as bad as it used to be.

Lock files are only needed because of version ranging. Maven worked fine without semantic versioning and lock files. Edit: Changed "semantic versioning" to "version ranging"

> Maven worked fine without semantic versioning and lock files.

No, it actually has the exact same problem. You add a dependency, and that dependency specifies a sub-dependency against, say, version `[1.0,)`. Now you install your dependencies on a new machine and nothing works. Why? Because the sub-dependency released version 2.0 that's incompatible with the dependency you're directly referencing. Nobody likes helping to onboard the new guy when he goes to install dependencies on his laptop and stuff just doesn't work because the versions of sub-dependencies are silently different. Lock files completely avoid this.

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#472

Post by zelphirkalt »

caconym_ wrote: post #227
hardwaregeek wrote: post #149

I gotta say, I feel pretty vindicated after hearing for years how Python’s tooling was just fine and you should just use virtualenv with pip and how JS must be worse, that when Python devs finally get a taste of npm/cargo/bundler in their ecosystem, they freaking love it. Because yes, npm has its issues but lock files and consistent installs are amazing

There is nothing I dread more within the general context of software development, broadly , than trying to run other people's Python projects. Nothing. It's shocking that it has been so bad for so long.

That's because many people don't pay attention to reproducibility of their developed software. If there is no lock file in a repo that nails the exact versions and checksums, then I already know it's likely gonna be a pain. That's shoddy work of course, but that doesn't stop people from not paying attention to reproducibility.

One could argue, that this is one difference between npm and such, and what many people use in the Python ecosystem. npm and cargo and so on are automatically creating lock files. Even people, who don't understand why that is important, might commit them to their repositories, while in the Python ecosystem people who don't understand it, think that committing a requirements.txt only (without checksums) is OK.

However, it is wrong, to claim, that in the Python ecosystem we didn't have the tools to do it right. We did have them, and that well before uv. It took a more care though, which is apparently too much for many people already.

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#473

Post by zelphirkalt »

ghusto wrote: post #359
tomaskafka wrote: post #342

Earlier quoted context omitted.

So many times I have come onto a library or tool that would fix my problem, and then realized “oh crap, it’s in Python, I don’t want to spend few hours building a brittle environment for it only for that env to break next time I need to use it” - and went to look for a worse solution in better language.

I really don't get this. I can count on no hands the number of times I've had problems simply going "pip install cool-thing-i-found". Sure, this is just my experience, but I use Python a lot and use a lot of tools written in Python.

This mentality is exactly what many people do wrong in Python. I mean, for a one-off, yes you can have setup instructions like that. But if you want things to work for other people, on other machines, you better include a lock file with checksums. And `pip install whatever` simply does not cut it there.

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#474

Post by bastawhiz »

NaomiLehman wrote: post #320
hardwaregeek wrote: post #149

I gotta say, I feel pretty vindicated after hearing for years how Python’s tooling was just fine and you should just use virtualenv with pip and how JS must be worse, that when Python devs finally get a taste of npm/cargo/bundler in their ecosystem, they freaking love it. Because yes, npm has its issues but lock files and consistent installs are amazing

conda was great to me

conda ruined my shell and never successfully worked for me. I guess YMMV

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#475

Post by andy99 »

nothrowaways wrote: post #103

Does speed really matter during python installation?

Possibly for some workflows, though personally I find the emphasis on speed baffling and a big part of the reason I don’t find most of these uv testimonials credible. I’m a regular python user across multiple environments and I’ve never considered waiting for pip to be a material part of my time, it’s trivial to the point of being irrelevant. The fact that so many people come out of the woodwork to talk about how fast it is, means either there’s some big group somewhere with a niche use case that gets them bogged down in pip dependency resolving or whatever gets sped up (obviously the actual downloading can’t be faster) or it’s just a talking point that (presumably) rust zealots who don’t actually use python arrive with en mass, but it’s honestly an extremely ineffective way of promoting the product to most python users who don’t have speed of package installation as anything close to a pain point.

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#476

Post by zelphirkalt »

hardwaregeek wrote: post #149

I gotta say, I feel pretty vindicated after hearing for years how Python’s tooling was just fine and you should just use virtualenv with pip and how JS must be worse, that when Python devs finally get a taste of npm/cargo/bundler in their ecosystem, they freaking love it. Because yes, npm has its issues but lock files and consistent installs are amazing

Tooling like npm, cargo, and others existed well before uv came up. I have used poetry years ago, and have had reproducible virtual environments for a long time. It's not like uv, at least in that regard, adds much. The biggest benefit I see so far, and that is also why I use it over poetry, is that it is fast. But the benefit of that is small, since usually one does not change the dependencies of a project that often, and when one does, one can also wait a few seconds longer.

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#478

Post by sheepscreek »

What about Pixi[1]? It has become an irreplaceable part of my dev stack. Fantastic for tool + library version management. It has replaced a number of tools for me and greatly simplified bootstrapping in a new environment (like lxc containers when I am experimenting with stuff) or creating a lightweight sandbox for AI agents.

1. https://pixi.sh/latest/

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#479

Post by okanat »

persedes wrote: post #460
warbaker wrote: post #407

Earlier quoted context omitted.

Have you figured out a good way to manage CUDA dependencies with uv?

https://docs.astral.sh/uv/guides/integration/pytorch/#using-... does that fit the bill?

Not the OP but does this actually package CUDA and the CUDA toolchain itself or just the libraries around it? Can it work only with PyTorch or "any" other library?

Conda packaging system and the registry is capable of understanding things like ABI and binary compatibility. It can resolve not only Python dependencies but the binary dependencies too. Think more like dnf, yum, apt but OS-agnostic including Windows.

As far as I know, (apart from blindly bundling wheels), neither PyPI nor Python packaging tools have the knowledge of ABIs or purely C/C++/Rust binary dependencies.

With Conda you can even use it to just have OS-agnostic C compiler toolchains, no Python or anything. I actually use Pixi for shipping an OS-agnostic libprotobuf version for my Rust programs. It is better than containers since you can directly interact with the OS like the Windows GUI and device drivers or Linux compositors. Conda binaries are native binaries.

Until PyPI and setuptools understand the binary intricacies, I don't think it will be able to fully replace Conda. This may mean that they need to have an epoch and API break in their packaging format and the registry.

uv, poetry etc. can be very useful when the binary dependencies are shallow and do not deeply integrate or you are simply happy living behind the Linux kernel and a container and distro binaries are fulfilling your needs.

When you need complex hierarchies of package versions where half of them are not compiled with your current version of the base image and you need to bootstrap half a distro (on all OS kernels too!), Conda is a lifesaver. There is nothing like it.

Re: Uv is the best thing to happen to the Python ecosystem in a decade

#480

Post by zmmmmm »

IshKebab wrote: post #428
zmmmmm wrote: post #260

> Instead of > > source .venv/bin/activate > python myscript.py > > you can just do > > > uv run myscript > This is by far the biggest turn off for me. The whole point of an environment manager is set the environment so that the commands I run work. They need to run natively how they are supposed to when the environment is set, not put through a translation layer. Side rant: yes I get triggered whenever someone tells…

You can still do the `source .venv/bin/activate` if you want. There's also `uv tool install` which will install things in your PATH without infecting your system with Python.

that makes me feel much better!
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