Apologies for not seeing the replies to this for a couple months!
Conveniently, I was just telling a colleague what problems I see it solving for us. Here's what I said:
1. A single answer to "how should I set up my python environment?". Previously it was, for example: should I use conda, or venv, or virtualenv, or what? should my project use requirements.txt or
requirements.in and pip-compile? Should we check in the requirements.txt after pip-compiling it? (I could go on like this for awhile 😅) Now we can have a single good answer for all of this across many projects.
2. Share code across many projects and libraries, without pip packaging and versioning. Change library code and application code in a single merge, rather than changing the library code with a version bump in an initial merge, waiting for the new package to build and publish, and then doing a second MR to get the changes into the application.
It is really (2) that makes the case, for me. But (1) is also very refreshing.