Mailu is a self-hosted mail server stack delivered as a set of Docker images.
It brings together the core services needed to run a modern mail platform, including web-based administration for domains and users, optional webmail front ends, account management features, and integrated mail security components for filtering and protecting messages.
This is free and open source software.
Key Features
- Supports core mail services including IMAP, SMTP and submission, with client auto-configuration profiles.
- Provides advanced mail handling with aliases, domain aliases, custom routing and full-text search of email attachments.
- Includes web access with an administration interface and support for multiple webmail front ends.
- Offers user-level tools such as auto-reply, auto-forward, fetched accounts and ManageSieve support.
- Includes security features such as enforced TLS, DANE, MTA-STS, Let’s Encrypt integration, outgoing DKIM signing, antivirus scanning and blocking of malicious attachments.
- Provides antispam protections including auto-learning, greylisting, DMARC, SPF and anti-spoofing measures.
- Includes a setup utility that can generate docker-compose.yml and mailu.env configuration files.
- Offers an optional RESTful API for automating configuration managed through the web administration interface.
Website: github.com/Mailu/Mailu
Support:
Developer: Mailu contributors
License: MIT License

Mailu is written in Python. Learn Python with our recommended free books and free tutorials.
Related Software
| Email Servers | |
|---|---|
| Exim | Highly configurable mail transfer agent |
| OpenSMTPD | Implementation of the server-side SMTP protocol with additional extensions |
| mox | Modern, secure, all-in-one email server |
| DBMail | Enables storing and retrieving mail messages from a database |
| WildDuck | Opinionated email server |
| Stalwart | All-in-one mail and collaboration server |
| Postfix | Popular mail transfer agent |
| Dovecot | Secure POP3 server that supports mbox and maildir mailboxes |
| Courier | Integrated mail/groupware server |
| Cyrus IMAP | Email, contacts and calendar server |
| Zimbra | Zimbra Collaboration Suite |
| Citadel | Exchange-killer groupware server |
| chasquid | SMTP server with a focus on simplicity, security, and ease of operation |
| Sendmail | Mail transfer agent for sophisticated mail configurations |
| qmail | Written as a more secure replacement for the Sendmail program |
| dma | DragonFly Mail Agent |
| DavMail | POP/IMAP/SMTP/Caldav/Carddav/LDAP exchange gateway |
Read our verdict in the software roundup.
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