Programming

Downside: "^1.2.3" as default versioning for libraries. You just pinned a version? Oh great, now I can't upgrade another library because you had to pin something in yours...

That non-standard syntax has been a PITA for the last few years. That being said: They created that syntax for regular applications (and not for libs) in a time when the pyproject.toml syntax was not anywhere near finalization.

Personally, I've found Poetry somewhat painful for developing medium-sized or larger applications (which I guess Python really isn't made for to begin with, but yeah).

Big problem is that its dependency resolution is probably a magnitude slower than it should be. Anytime we changed something about the dependencies, you'd wait for more than a minute on its verdict. Which is particularly painful, when you have to resolve version conflicts.

Other big pain point is that it doesn't support workspaces or multi-project builds or whatever you want to call them, so where you can have multiple related applications or libraries in the same repo and directly depending on each other, without needing to publish a version of the libraries each time you make a change.

When we started our last big Python project, none of the Python tooling supported workspaces out of the box. Now, there's Rye, which does so. But yeah, I don't have experience yet, with how well it works.