docker-mailserver (DMS) packages a complete, production-grade mail server into a single container. It uses the standard, battle-tested components, and replaces a database and web panel with plain configuration files, which makes it easy to version, back up, and upgrade.

Components

Job	Software
Sending and receiving (SMTP)	Postfix, with Postscreen
Mailboxes (IMAP, POP3), filters, quotas	Dovecot, with Sieve
Spam filtering	Rspamd or SpamAssassin, plus Postgrey
Antivirus	ClamAV
Signing and policy	OpenDKIM, OpenDMARC, SPF
Brute-force protection	Fail2ban
Certificates	Let’s Encrypt integration
Fetching from other accounts	Fetchmail, Getmail

LDAP and OAuth2 authentication are also supported.

How you manage it

There is no web UI. You manage accounts, aliases, and DKIM keys with the setup script inside the container, and everything else through config files mounted into it:

docker exec -it mailserver setup email add user@example.com
docker exec -it mailserver setup config dkim

The documentation is thorough and covers DNS records, ports, and security in detail.

Before you self-host email

Running a mail server is very doable with DMS, but deliverability is the hard part: your server’s IP needs a good reputation, correct reverse DNS, and properly published SPF, DKIM, and DMARC records, and some residential and cloud IP ranges are blocked outright. Read why self-hosted email is hard first. Many people use DMS for receiving and storage while sending through a relay.

Alternatives

• Mailcow: similar components with a full web UI and groupware
• Mox: a single Go binary that automates much of the setup
• Stalwart: a modern all-in-one mail server in Rust
• Mail-in-a-Box: an opinionated appliance for a dedicated server

For webmail on top, add Roundcube or SnappyMail.

License

MIT.

Links

• Repository
• Documentation