Postgres is a db and Dovecot is a IMAP/POP thing. Exim is a MTA and I think you meant to say Postfix 8) I personally use Exim. The developers of both have co

Postgres is a db and Dovecot is a IMAP/POP thing. Exim is a MTA and I think you meant to say Postfix 8) I personally use Exim. The developers of both have collaborated as required with each other in the past over certain issues and both projects are very mature. They are rather different beasts and there are loads of articles out there comparing them.