Some notes on using `uv` for Glasgow firmware tasks

[thoughtpolice]

This is more a report that uv works with Glasgow, and that it might be nice to add some documentation about it to the main page, somehow, maybe, if it seems reasonable.

For background, I'm not really a skilled Pythonista in the sense I have always found it very annoying to understand all the differences between various package tools and also the most reliable way to distribute Python or run one-off Python scripts and tools (without venv management, which I think is sort of a vestigial process that has remained in place, from a prior decade when sandboxed/hermetic tooling was far different and much clunkier.) uv however has been an extreme breath of fresh air and I've used it a lot because it makes running one offs so much easier, it has effectively totally changed my ability to use Python reliably, as it brings dependency management way into the 2020s. (It is extremely hyped up online, but I can personally say it actually is really good and deserving of it?)

I decided to upgrade my Glasgow's firmware this weekend to use it on a project. I normally do everything through Nix, but there isn't currently a binary build of a recent glasgow package for aarch64-linux, for my Asahi Linux laptop. Normally I'd fix this, but I have many things to do. And I've never used pipx/pdm or any of these other tools; I decided to try uv. Here's what I did, on aarch64-linux on an M2 Air:

0. Read the documentation.
1. Run nix shell nixpkgs#{uv,libusb1} which just adds those things to $PATH because I need them
2. Clone the glasgow source code && cd glasgow/software
3. Do the udev stuff that was mentioned.
4. uv run --python 3.11 --extra builtin-toolchain glasgow list
5. Done. Every glasgow command seemed to actually work fine. I even updated my firmware this way!

Step 1 can be replaced by whatever distro-specific thing you like. I think step 2 can even by skipped entirely, if you perform the right uv incantation pointing it to the remote source repo. Maybe. Beyond that, I needed no changes to anything for this to work, and from start to finish this process was about 90 seconds long and I got going, and it instantly worked with the pdm lockfile.

I currently am still playing around but wanted to report this here. I might add more comments here as I keep playing with things. If anyone searches up how to use uv with Glasgow, then hopefully they'll end up here.

[thoughtpolice]

Also, while using uv run, it spat out this very interesting and informative warning about a nit in the lockfile:

a@sheik ~/s/g/software ((c8d9329b)) [2]> uv run --python 3.11 --extra builtin-toolchain glasgow flash
warning: The `requires-python` specifier (`~=3.11`) in `glasgow` uses the tilde specifier (`~=`) without a patch version. This will be interpreted as `>=3.11, <4`. Did you mean `~=3.11.0` to constrain the version as `>=3.11.0, <3.12`? We recommend only using the tilde specifier with a patch version to avoid ambiguity.

I'm not sure if this warning is correct, but it seems reasonable and certainly believable, and it is at least a little annoying. :) I don't have pdm installed so I didn't regenerate the lockfile or anything to test it, but if this is accurate I think it's probably worth fixing!

[whitequark]

I've actually tested uv recently. The reason we recommend pdm is that the advantages of pdm are exactly the same as the advantages of uv that you accurately list here (indeed, these reasons are why I picked pdm), but:

1. When I made the choice, uv did not exist yet.
2. Having two near-identical options is worse than having one. (More testing workload, more support workload, etc.)

The main reason to use uv is that it's a fair bit faster, but this isn't a huge deal for Glasgow. (There is a pdm mode where it uses uv for dependency resolution, but it's not reliable yet.)

I've also seen the warning and I'm happy to merge a PR fixing the bounds.

[whitequark]

Also if you just want to update the firmware, we have https://glasgowembedded.github.io/glasgow-webusb/ (preview version) which is plug&play on Chrome

[thoughtpolice]

Right, I basically came at it from the opposite direction; my knowledge of Python dependency management is something like "learned about venvs in 2012" and then "learned about uv in 2025" so anything between is as good as a mystery to me.

I also saw news about the WebUSB port, but at least for the firmware update wanted to do that locally, but with that out of the way I'll be using both routes. :) Are you actively taking bug reports for the WebUSB port yet?

[whitequark]

Check the README for the WebUSB repo, it's probably a known issue. I'd say report the errors in the IRC/Matrix room for now.

[mayjack0312]

I recently discovered a very interesting language Rust, and I am trying to use it to write the host computer of Glasgow.

[flokli]

I decided to upgrade my Glasgow's firmware this weekend to use it on a project. I normally do everything through Nix, but there isn't currently a binary build of a recent glasgow package for aarch64-linux, for my Asahi Linux laptop. […]

This recently changed: NixOS/nixpkgs#382355 (comment)

[obvious-burner]

Also worth noting, uv can handle Glasgow just fine as a command-line tool. One can either install it as editable for quick development, just like with pipx (--editable requires a local directory, hence the git clone first):

$ git clone --depth=1 https://github.com/GlasgowEmbedded/glasgow && uv tool install --editable glasgow/software[builtin-toolchain]

...or install it for general use (using the #subdirectory=... syntax to select the software/ dir)...

$ uv tool install git+https://github.com/glasgowembedded/glasgow/#subdirectory=software

...or even run it without formally installing it, if you want to for some reason (since you'd still have to set up udevd rules):

$ uvx --from git+https://github.com/glasgowembedded/glasgow#subdirectory=software glasgow -V
   Built glasgow @ git+https://github.com/glasgowembedded/glasgow@8b021305f059fae685fe862c9b73399dc2f09f21#subdirectory=software
Installed 14 packages in 12ms
Glasgow 0.1.dev2617+g8b02130 (CPython 3.13.3 on Linux-6.12.25-amd64-x86_64-with-glibc2.41)

(As for updating: editable install, pull down the latest commit, then uv tool update glasgow. Just the latter command if using a non-editable install. Doesn't get much simpler than that.)