Used to manage it all manually, set up https://mailcow.email/ after a server move a couple years ago. It's been great, running inside docker now via docker-compose alongside https://github.com/JrCs/docker-letsencrypt-nginx-proxy-compa... for automatic letsencrypt for the web interface along with my additional web services hosted on the same server. I had one minor hiccup when upgrading wherein I had to restart all docker containers, that's about it in terms of maintenance.