for anyone interested, 'spamassassin-milter' https://gitlab.com/glts/spamassassin-milter
a modern/current, rust-coded, SpamAssassin milter -- that cleanly submits msgs via spamc to spamd -- is, for me, working quite nicely with current/latest Postfix. it appears to be lightweight, fast & stable, so far. it's free of some of the restrictions of spamass-milter; for me, notably, the limited headers passed. the dev has been very helpful/responsive/courteous to date, and is focussed on ensuring it works with Postfix; much appreciated! i've switched a couple of servers to using it in production; watching logs for awhile. it currently sits at the end of my milter-chain, opendkim -> opendmarc -> milter-regex -> clamav-milter -> spamassassin-milter if all continues to goe well, I'll 'jump-ship' wholesale to its use soon. atm, it's a DIY-build, though trivial. prereqs include sendmail-devel (libmilter) cargo rust here i've cargo -V cargo 1.43.0 rustc -V rustc 1.43.0 the build/install is straightforward git clone https://gitlab.com/glts/spamassassin-milter cd spamassassin-milter note: edit milter.pc to your needs/liking then build PKG_CONFIG_PATH=. cargo build move the excutable somewhere useful cp -af target/debug/spamassassin-milter /usr/local/sbin/ set up a service file; mine's /etc/systemd/system/spamassassin-milter.service [Unit] Description=SpamAssassin Milter Wants = spamd.service After = syslog.target local-fs.target network-online.target spamd.service Before = postfix.service [Service] Type=simple UMask = 0117 User=spamassassin-milter Group=postfix-milter PIDFile=/run/spamassassin-milter/spamassassin-milter.pid ExecStart=/usr/local/sbin/spamassassin-milter \ --verbose \ --trusted-networks '...' \ --max-message-size 100000000 \ --reject-spam \ --reply-code '550' \ --reply-status-code '5.7.1' \ --reply-text 'Service unavailable; REJECTED: Message Content' \ unix:/run/spamassassin-milter/spamassassin-milter.sock Restart=on-failure [Install] WantedBy=multi-user.target make sure your chosen user:group exist & match the service file enable/start the milter service (and of course spamd) if interested, join in at the github project. strength in numbers, rt?