“Run Your Own Mail Server” technology stack

I’ve churned through much of the general stuff about email, and am about to dive into specific configurations and examples. In some ways, the protocol background is the hardest part of any book. Orienting the reader to understand the configuration examples and make their own decisions is a pain–though front-loading the hard stuff simplifies writing the rest of the book.

But this means I need to make final decisions on the book’s technology stack.

Postfix (backed with MariaDB) and Dovecot are abs...