Email-Server betreiben…
https://cfenollosa.com/blog/after-self-hosting-my-email-for-twenty-three-years-i-have-thrown-in-the-towel-the-oligopoly-has-won.html F*ck Google, Micro$oft
https://vadosware.io/post/its-never-been-easier-or-harder-to-self-host-email/