@maple Dovecot + Postfix would do the job and aside from their dependencies I don't think there's anything else you'd NEED to install. While not strictly necessary, it'd be a Good Server Administrator thing to harden Postfix's configuration to make sure it's not an open relay.
I'd personally recommend getting a TLS cert (letsencrypt would certainly do) and using IMAPS and SMTP-over-TLS instead of the clear-text versions of the protocols. But again, not absolutely necessary.
It's been a couple of years since I last set up either Postfix or Dovecot, but I remember them both being fairly plug-and-play out of the box on Debian and its derivatives. I just found and read through these guides; while Debian/Ubuntu-centered, they seem comprehensive:
And for spam filtering, I've used Spamassassin for the last 20-ish years; this guide does a decent job explaining that:
@maple All the extra packages recommended in that guide on akadia should be automatic dependencies when you install spamassassin from the repos; no need to actually install everything by hand or from source unless that's your kind of thing.
@devlogic thank you!
@maple You're welcome; hope it works out for you!
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