Evaluate mailu as a potential solution to our problem.
They already have a kubernetes deployment and it now uses Postgres as a database instead of SQLite. It has all the features we need. To be able to use it, there are 2 things missing:
- SSO integration https://github.com/Mailu/Mailu/issues/855
- API: https://github.com/Mailu/Mailu/issues/445
I'd be glad to get your feedback :)