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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

#171

Post by wtallis »

vindex10 wrote: post #76
kyt wrote: post #21

I must be the odd man out but I am not a fan of uv. 1. It tries to do too many things. Please just do one thing and do it well. It's simultaneously trying to replace pip, pyenv, virtualenv, and ruff in one command. 2. You end up needing to use `uv pip` so it's not even a full replacement for pip. 3. It does not play well with Docker. 4. It adds more complexity. You end up needing to understand all of these new enviro…

I would also add UV_NO_SYNC as smth I had to learn. It comes in combination with uv pip

What's your use case for UV_NO_SYNC? I assume the option exists for a reason, but aside from maybe a modest performance improvement when working with a massive complex package environment, I'm not sure what problem it solves.

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

#172

Post by Rogach »

moleperson wrote: post #124
LeoPanthera wrote: post #18

For single-file Python scripts, which 99% of mine seem to be, you can simplify your life immensely by just putting this at the top of the script: #!/usr/bin/env -S uv run --script # /// script # requires-python = ">=3.11" # dependencies = [ "modules", "here" ] # /// The script now works like a standalone executable, and uv will magically install and use the specified modules.

Why is the ‘-S’ argument to ‘env’ needed? Based on the man page it doesn’t appear to be doing anything useful here, and in practice it doesn’t either.

Without -S, `uv run --script` would be treated as a binary name (including spaces) and you will get an error like "env: ‘uv run --script’: No such file or directory".

-S causes the string to be split on spaces and so the arguments are passed correctly.

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

#173

Post by oblio »

j45 wrote: post #115
aerhardt wrote: post #26

I'm surprised by how much I prefer prepending "uv" to everything instead of activating environments - which is still naturally an option if that's what floats your boat. I also like how you can manage Python versions very easily with it. Everything feels very "batteries-included" and yet local to the project. I still haven't used it long enough to tell whether it avoids the inevitable bi-yearly "debug a Python enviro…

This isn't a comment just about Python.. but it should just work. There shouldn't be constant ceremony for getting and keeping environments running.

There are basically 0 other programming languages that use the "directory/shell integration activated virtual environment", outside of Python.

How does the rest of the world manage to survive without venvs? Config files in the directory. Shocking, really :-)))

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

#174

Post by FattiMei »

But what was wrong with pip, venv and pyproject.toml in the first place? I just keep a system installation of python for my personal things and an environment for every project I'm working on. I'd get suspicious if a developer is picky about python versions or library versions like what crazy programs are you writing?

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

#175

Post by an_guy »

collinmanderson wrote: post #155
an_guy wrote: post #144

All these comments look like advertisement. "uv is better than python!!", "8/10 programmers recommend uv", "I was a terrible programmer before but uv changed my life!!", "uv is fast!!!"

> All these comments look like advertisement. "uv is better than python!!", "8/10 programmers recommend uv", "I was a terrible programmer before but uv changed my life!!", "uv is fast!!!" Have you tried uv?

Why would I? Does it offer something that standard python tools doesn't? Why uv over, lets say, conda?

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

#176

Post by tclancy »

kyt wrote: post #21

I must be the odd man out but I am not a fan of uv. 1. It tries to do too many things. Please just do one thing and do it well. It's simultaneously trying to replace pip, pyenv, virtualenv, and ruff in one command. 2. You end up needing to use `uv pip` so it's not even a full replacement for pip. 3. It does not play well with Docker. 4. It adds more complexity. You end up needing to understand all of these new enviro…

So I have been doing Python for far too long and have all sort of tooling I've accreted to make Python work well for me across projects and computers and I never quite made the leap to Poetry and was suspicious of uv.

Happened to buy a new machine and decided to jump in the deep end and it's been glorious. I think the difference from your comment (and others in this chain) and my experience is that you're trying to make uv fit how you have done things. Jumping all the way in, I just . . . never needed virtualenvs. Don't really think about them once I sorted out a mistake I was making. uv init and you're pretty much there.

>You end up needing to use `uv pip` so it's not even a full replacement for pip

The only time I've used uv pip is on a project at work that isn't a uv-powered project. uv add should be doing what you need and it really fights you if you're trying to add something to global because it assumes that's an accident, which it probably is (but you can drop back to uv pip for that).

>`UV_TOOL_BIN_DIR`, `UV_SYSTEM_PYTHON`, `UV_LINK_MODE`, etc.

I've been using it for six months and didn't know those existed. I would suggest this is a symptom of trying to make it be what you're used to. I would also gently suggest those of us who have decades of Python experience may have a bit of Stockholm Syndrome around package management, packaging, etc.

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

#177

Post by Narushia »

kyt wrote: post #21

I must be the odd man out but I am not a fan of uv. 1. It tries to do too many things. Please just do one thing and do it well. It's simultaneously trying to replace pip, pyenv, virtualenv, and ruff in one command. 2. You end up needing to use `uv pip` so it's not even a full replacement for pip. 3. It does not play well with Docker. 4. It adds more complexity. You end up needing to understand all of these new enviro…

uv has played well with Docker in my experience, from dev containers to CI/CD to production image builds. Would be interested to hear what is not working for you.

The uv docs even have a whole page dedicated to Docker; you should definitely check that out if you haven't already: https://docs.astral.sh/uv/guides/integration/docker/

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

#178

Post by jvanderbot »

dekhn wrote: post #58

I hadn't paid any attention to rust before uv, but since starting to use uv, I've switched a lot of my performance-sensitive code dev to rust (with interfaces to python). These sorts of improvements really do improve my quality of life significantly. My hope is that conda goes away completely. I run an ML cluster and we have multi-gigabyte conda directories and researchers who can't reproduce anything because just to…

Obligatory: Not only rust would be faster than python, but Rust definitely makes it easy with Cargo. Go, C, C++ should all exhibit the performance you are seeing in uv, if it had been written in one of those languages.

The curmudgeon in me feels the need to point out that fast, lightweight software has always been possible, it's just becoming easier now with package managers.

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

#179

Post by gigatexal »

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

the thing is I never had issues with virtual environments -- uv just allows me to easily determine what version of python that venv uses.

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

#180

Post by icedchai »

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

poetry gave us lock files and consistent installs for years. uv is much, much faster however.
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