There are only two hard things in Computer Science: cache invalidation and naming things. — Phil Karlton

I don’t think there is anyone on the planet who renames things as much as I do. Stop it. Seriously. Its not worth it.

It looks innocuous. But it isn’t.

I had a project that was working just fine but being me I renamed the directory and all of a sudden everything stopped working. Turns out it was a Python project using uv (you run into same problem if you use poetry). uv hardcodes the path in .venv/bin/activate. Look for this line:

VIRTUAL_ENV='/path/to/.venv'

So if you rename a directory and then run source .venv/bin/activate or any other uv command, it will stop working!

It doesn’t end there. I was using uvicorn and the path is hardcoded in that too. What makes it hard to debug is that the errors you get are extremely cryptic like File not found when you can see it right in front of your eyes.