This was a really nice and detailed writeup, what a wonderful read! For my own needs, I essentially let others do the heavy lifting and used docker-mailserver,

This was a really nice and detailed writeup, what a wonderful read! For my own needs, I essentially let others do the heavy lifting and used docker-mailserver, which includes Postfix, Dovecot and some other software in an easy to deploy package: https://docker-mailserver.github.io/docker-mailserver/latest/introduction/ https://docker-mailserver.github.io/docker-mailserver/latest... Actually, that documentation of theirs is a nice read as well! I've been using this for a low volume of mails for a few years and haven't had much in the way of issues, deliverability, or otherwise. I even got lazy to the point of only configuring SPF, not DKIM or DMARC and have no problems there either (though that might change in the future). Throwing something like a Roundcube container into the mix when I need a web UI is exceedingly easy as well, as is setting up Apache (with mod_md), Nginx (with certbot) or Caddy as a reverse proxy.