I like the "venv per script" approach. So it is like... you create a directory that contains main.py and foo.pdm or whatever its extension is, and then it grabs all the dependencies into that directory when you run a command and has a lock file and everything? I did not check out the website yet, that is why I am asking. If this is the case, then it is a win in my book.

Yes, PDM does some hacks to make it work with the familiar `python` executable. See the example at https://github.com/pdm-project/pdm/#quickstart. All you need is a fews lines to set up your shell.