Addendum: this post has a sequel
Whenever I have to interact with email software that isn't OpenSMTPD I'm just so appalled by how shitty it is. Except maybe rspamd. Email software just seems to follow the 1980s Unix philosophy of "do one thing and completely suck dick at it".
My entire config looks like this:
pki mikejsavage.co.uk certificate "/etc/ssl/mikejsavage.co.uk.fullchain.pem"
pki mikejsavage.co.uk key "/etc/ssl/private/mikejsavage.co.uk.key"
listen on lo
listen on lo port 10028 tag DKIM
listen on egress tls pki mikejsavage.co.uk
listen on egress port 587 tls-require pki mikejsavage.co.uk auth
accept from any for local virtual { "@" => mike } deliver to mda "rspamc --mime --ucl --exec /usr/local/bin/dovecot-lda-mike" as mike
accept from local tagged DKIM for any relay
accept from local for any relay via smtp://127.0.0.1:10027
That's 9 lines of config. DKIMProxy's config is 8 lines. Dovecot's config is 2453 lines split across 34 files. WTF how can you suck so much? DKIMProxy's only job is to add a header to outgoing emails. Dovecot is probably of similar complexity to smtpd but has two orders of magnitude more config. I have a bunch of spamd/bgpd garbage lying around too and I have no idea if it does anything. Nuts.
pop3d looks extremely good, like this is how Dovecot should be, but it's POP and POP is useless. God damn. It's made me pretty tempted to do an imapd though. I'd have to keep Dovecot around for the MDA until smtpd gets filters, but after that I could drop everything but smtpd/rspamd/imapd and be happy.
The gmail spam filter does an extremely bad job of dealing with modern spam. The spam of old times is pretty much solved, the spam I got on this domain before I set up rspamd was all obviously fake invoices and Russian dating websites, really simple to filter out.
Modern spam is also trivial to spot, but the people spamming buy ads from Google so they'll never block it. I mean crap like newsletters after you explicitly unchecked the box that allows them to send you junk, the biweekly terms and conditions updates from shit startups, etc. If you blocked any email that contains an unsubscribe link or the phrase "Terms and Conditions" you would catch 100% of it with nearly no false positives. It's so easy but they won't do it.
Amusingly the gmail spam filter does a perfect job on my work inbox:
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Mike - Invitation to discuss how ex-Google/McKinsey team is replacing HR with bots
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