I've actually "ported" Django's auth system (including their email verification pieces) to actix-web, and reused it across a few projects. I've thought about open sourcing it, but the problem is... well, then you have to maintain it, and I'm not really interested in doing that.
But if someone wants to take up the project I don't mind donating the code.
If anyone ever saw my version years ago[1], it's effectively Jelly 2.0.