> you may pull apart the monlithic server and run inbound processing, filtering, IMAP access and outbound queueing as separate processes or even on separate systems.
Can this be done without forking source code? E.g. just configuring two instances.
Thanks for the link to FAQ. Actually, simple, no bloat’ little dependency software definitely has some appeal.
This page shows how to configure maddy to only handle SMTP: https://foxcpp.dev/maddy/tutorials/smtp-only/ You can follow it but swap Dovecot for another maddy instance, configured as shown here: https://foxcpp.dev/maddy/tutorials/imap-only/
This works because maddy implements both client and server for Dovecot's SASL delegation protocol.
Alternatively you can configure pass_table to read from shared SQL database. Hm, maddy-tables(5) man page is not rendered on the website but you can look at sql_query module.