Just spamassassin and postgrey that ship with mail-in-a-box (https://github.com/mail-in-a-box/mailinabox https://github.com/mail-in-a-box/mailinabox). I had an

Just spamassassin and postgrey that ship with mail-in-a-box (https://github.com/mail-in-a-box/mailinabox https://github.com/mail-in-a-box/mailinabox). I had an issue last year with it not detecting or learning a particular Russian spammer but as of ~4 months ago they all now correctly go to spam. Otherwise it's been very good.