uv run --project doesn't allow resolving module imports on windows

[leokeba]

Summary

In my python project, I have a scripts folder where I keep various utilities that need to import code from the main app folder. When running it on macOS, I just use uv run scripts/test.py --project . and everything works as expected. On my windows system, when I try uv run scripts\test.py --project . i get the following error : ModuleNotFoundError: No module named 'app'.

I tried using an absolute path instead and various tricks to make it work, and also using the --folder argument instead, but nothing helps. Am I misunderstanding something or is this a bug ?

Platform

Windows 11 x86_64

Version

0.6.6

Python version

3.13.2

[nbaju1]

Isn't --project . the same as running without the flag, since the default behavior is to look for the project within the current directory? If so do you get the same result without it?

[leokeba]

Isn't --project . the same as running without the flag, since the default behavior is to look for the project within the current directory? If so do you get the same result without it?

On macOS, running a script from a subfolder breaks module imports from the rest of the app as the python interpreter runs from the subfolder environment instead of the root project folder. The solution I found to this issue was using the --project . flag, but this only works on macOS.

On windows, both give the same result, which is the following error : ModuleNotFoundError: No module named 'app'

In my opinion, the best solution would be not needing to use the --project . flag at all regardless of the OS or subfolder structure, but I figure there might be a reason things work that way.

[nbaju1]

Not able to reproduce on Windows 11.

Folder structure:

project/
├── app/
|   └── foo.py
├── scripts/
|   └── test.py
└── pyproject.toml

foo.py

def bar():
    print("bar")

test.py

from app.foo import bar

bar()

Running uv run .\scripts\test.py (without or without --project .) from the root outputs bar.

[leokeba]

I reproduced your example and still get the same error on Windows 11.

What are the contents of your pyproject.toml ?

[nbaju1]

pyproject.toml

[project]
name = "project"
version = "0.1.0"
description = "Project"
requires-python = ">=3.12"

Note that I have placed the venv inside the project root and it is active before running the command, if that matters.
Edit: Scratch that. Deleted the venv and recreated it, now I get the same error as you. Old venv on my end it seems.

[leokeba]

The only difference is that I was using python 3.13 instead of 3.12, but i tried changing the version and I still get the same result.

I am using a .venv placed in the project root as well. Any ideas for a workaround ?

[nbaju1]

Adding this to the pyproject.toml file

[project.scripts]
test = "scripts.test:main"

[build-system]
requires = ["uv_build"]
build-backend = "uv_build"

[tool.uv.build-backend]
module-root = ""
module-name = "app"

(placing the bar() call in a main function in test.py) and running uv run test works though (in uv v0.6.7)

[leokeba]

Thanks a lot, this solution does indeed fix all my issues on both OSes, and it is much more elegant than what I was doing before.

You can close this issue if everything else is expected behaviour.