I am still working on it but the main issue is psycopg support for now, as I had to install psycopg2cffi in my test environment, but it will probably prevent me from using pypy for running our test suite, because psycopg2cffi does not have the same features and versions as psycopg2. This means either we switch our prod to pypy, which won't be possible because I am very new in this team and that would be seen as a big, risky change by the others, or we keep in mind the tests do not run using the exact same runtime as production servers (which might cause bugs to go unnoticed and reach production, or failing tests that would otherwise work on a live environment).
I think if I ever started a python project right now, I'd probably try and use pypy from the start, since (at least for web development) there does not seem to be any downsides to using it.
Anyways, thank you very much for your hard work !