Self-hosted email solutions

Here are some good, self-hostable and all-in-one email server projects I’ve encountered.

• Mail-in-a-Box: too opinionated out of the box.
• Posteo.
• Docker based:
  • Docker mail-server: Decent number of maintainers, decently lightweight (for e.g., 2GB RAM), secure enough etc. No web UIs.
  • Mailcow. Requires ~8 GB RAM though.
  • Mailu.
• Modoboa.
• The following look interesting but are maintained by a single maintainer (something that I’d like to avoid):
  • Maddy.
  • Mox - looks lightweight.
  • Stalwart - again, lightweight plus modern.

However, in my limited experience of couple of months, there is a lot that can go wrong while self-hosting email, especially things that aren’t in your control. So, apart from intellectual curiosity or if you are getting paid, there is no good reason to go this route.