@algernon I run my own email server. It's definitely good for preserving email as an actually federated, decentralized system. It's kind of a pain these days though. Major kudos to you if you do it, and good luck!
@algernon Yeah, there's several things you have to do... DKIM and all that... LetsEncrypt at least makes the ssl part easier... it's also just IME a lot of small pieces to hook together to get a good system. I use Dovecot + Postfix + SpamAssassin's spamd + mu4e.