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Switching from Pyenv to Uv

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Re: Switching from Pyenv to Uv

#111

Post by synergy20 »

fluidcruft wrote: post #80
quickslowdown wrote: post #15

I highly, highly recommend uv. It solves & installs dependencies incredibly fast, and the CLI is very intuitive once you've memorized a couple commands. It handles monorepos well with the "workspaces" concept, it can replace pipx with "uv tool install," handle building & publishing, and the docker image is great, you just add a FROM line to the top and copy the bin from /uv. I've used 'em all, pip + virtualenv, conda…

I generally agree but one thing I find very frustrating (i.e. have not figured out yet) is how deal with extras well, particularly with pytorch. Some of my machines have GPU, some don't and things like "uv add" end up uninstalling everything and installing the opposite forcing a resync with the appropriate --extra tag. The examples in the docs do things like CPU on windows and GPU on Linux but all my boxes are linux.…

i use uv+torch+cuda on linux just fine,never used the extra flag, i wonder what's the problem here?

Re: Switching from Pyenv to Uv

#113

Post by marcthe12 »

TheIronYuppie wrote: post #68

For scripting... HIGHLY recommend putting your dependencies inline. E.g.: #!/usr/bin/env python3 # /// script # requires-python = ">=3.11" # dependencies = [ # "psycopg2-binary", # "pyyaml", # ] # /// Then - uv run -s file.py

Do you need a wrapper script for scripts in the PATH or execve? I would usualy chmod+x the script but I am not sure here.

Re: Switching from Pyenv to Uv

#114

Post by shawnz »

fluidcruft wrote: post #80
quickslowdown wrote: post #15

I highly, highly recommend uv. It solves & installs dependencies incredibly fast, and the CLI is very intuitive once you've memorized a couple commands. It handles monorepos well with the "workspaces" concept, it can replace pipx with "uv tool install," handle building & publishing, and the docker image is great, you just add a FROM line to the top and copy the bin from /uv. I've used 'em all, pip + virtualenv, conda…

I generally agree but one thing I find very frustrating (i.e. have not figured out yet) is how deal with extras well, particularly with pytorch. Some of my machines have GPU, some don't and things like "uv add" end up uninstalling everything and installing the opposite forcing a resync with the appropriate --extra tag. The examples in the docs do things like CPU on windows and GPU on Linux but all my boxes are linux.…

Getting the right version of PyTorch installed to have the correct kind of acceleration on each different platform you support has been a long-standing headache across many Python dependency management tools, not just uv. For example, here's the bug in poetry regarding this issue: https://github.com/python-poetry/poetry/issues/6409

As I understand it, recent versions of PyTorch have made this process somewhat easier, so maybe it's worth another try.

Re: Switching from Pyenv to Uv

#115

Post by tempay »

kyawzazaw wrote: post #99
o10449366 wrote: post #63

If uv figures out a way to capture the scientific community by adding support for conda-forge that'll be the killshot for other similar projects, imo. Pixi is too half-baked currently and suffers from some questionable design decisions.

which subfield of scientific community uses that? and for what purpose, if you could summarize

The key thing of conda-forge is that it's language (rust/go/c++/ruby/java/...) and platform (linux/macos/win/ppc64le/aarch64/...) agnostic rather than being python only.

If you want you can depend on a C++ and fortran compiler at runtime and (fairly) reliably expect it to work.

Re: Switching from Pyenv to Uv

#117

Post by uasi »

mcintyre1994 wrote: post #65
quickslowdown wrote: post #15

I highly, highly recommend uv. It solves & installs dependencies incredibly fast, and the CLI is very intuitive once you've memorized a couple commands. It handles monorepos well with the "workspaces" concept, it can replace pipx with "uv tool install," handle building & publishing, and the docker image is great, you just add a FROM line to the top and copy the bin from /uv. I've used 'em all, pip + virtualenv, conda…

That scripting trick is awesome! One of the really nice things about Elixir and its dependency manager is that you can just write Mix.install(…) in your script and it’ll fetch those dependencies for you, with the same caching you mentioned too. Does uv work with Jupyter notebooks too? When I used it a while ago dependencies were really annoying compared to Livebook with that Mix.install support.

uv offers another useful feature for inline dependencies, which is the exclude-newer field[1]. It improves reproducibility by excluding packages released after a specified date during dependency resolution.

I once investigated whether this feature could be integrated into Mix as well, but it wasn't possible since hex.pm doesn't provide release timestamps for packages.

> Does uv work with Jupyter notebooks too?

Yes![2]

[1] https://docs.astral.sh/uv/guides/scripts/#improving-reproduc... [2] https://docs.astral.sh/uv/guides/integration/jupyter/

Re: Switching from Pyenv to Uv

#118

Post by pzo »

js2 wrote: post #108
pzo wrote: post #105

I want to switch to uv from pyenv but one use case that didn't manage to figure out is if I can have similar setup like pyenv that I install few python version and setup one to be a global default (configured in zsh). I know for bigger projects proper way is to setup virtual environment for all new project but I do many mini (throwaway) python scripts and experiments or testing repos in python and would be really ann…

Yes, uv is well suited to that use case by declaring your Python version and/or dependencies right in the script itself: https://docs.astral.sh/uv/guides/scripts/#declaring-script-d... You can use an alternate shebang line so you can run the script directly: #!/usr/bin/env -S uv run --script # /// script # requires-python = ">=3.12" # dependencies = [ # "requests", # "typer-slim", # ] # /// import requests import typ…

Yes but I then still then have to declare all dependencies for all tiny throwaway script, right now I have global python in pyenv and installed tons of plugins and didn't have too much issues with conflicts so was good enough for me

Re: Switching from Pyenv to Uv

#119

Post by baq »

javchz wrote: post #40
IshKebab wrote: post #29

Uv really fixes Python. It takes it from "oh god I have to fight Python again" to "wow it was actually fast and easy". I think all the other projects (pyenv, poetry, pip, etc.) should voluntarily retire for the good of Python. If everyone moved to Uv right now, Python would be in a far better place. I'm serious. (It's not going to happen though because the Python community has no taste.) The only very minor issue I'v…

Agree. I mostly do front end in my day job, and despite JavaScript being a bit of a mess lang, dealing with npm is way better than juggling anaconda, miniforge, Poetry, pip, venv, etc depending on the project. UV is such a smooth UX that it makes you wonder how something like it wasn’t part of Python from the start.

+1

…but we did have to wait for cargo, npm (I include yarn and pnpm here) and maybe golang to blaze the ‘this is how it’s done’ trail. Obvious in hindsight.

Re: Switching from Pyenv to Uv

#120

Post by Kwpolska »

__MatrixMan__ wrote: post #76
0cf8612b2e1e wrote: post #39

Earlier quoted context omitted.

Pfft. Pull the other one. The PSF hates the idea of dealing with something so icky. I have been pretty pleased with uv, but I am continually worried about the funding model. What happens when the VC starts demanding a return?

We fork it. Whatever carrot the VC's dangle can be chased by the handful who care, and the rest of us can continue using the important part.

Ah, so that's why it's written in Rust. Less people who care about Python packaging are capable of forking it.
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