Block a user
rspamd milter integration (optional)
Connection-level blocklist (IP deny list)
Rate limiting on SMTP connections
Log shipping / structured access logs
Metrics endpoint (Prometheus)
Alias support (forward
info@ → real mailbox)
Admin HTTP API (manage domains, mailboxes, aliases)
DNSBL checks on inbound connections (basic blocklist)
Reject or quarantine based on DMARC policy
DMARC policy parsing and enforcement
SPF record lookup and enforcement
DKIM verification on inbound mail
DKIM signing on outbound mail
Auto-renew via ACME / Let's Encrypt (optional)
Domain and mailbox management (add/remove)