Docker Mailserver vs Mailu
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Docker Mailserver | Mailu |
|---|---|---|
| Deploy effort | ≈5-minute setup | Under-an-hour setup |
| Health score | 96 · Excellent | 91 · Excellent |
| Category | Mail Servers | Mail Servers |
| License | MIT | MIT |
| Language | Shell | Python |
| Setup difficulty | Medium | Medium |
| Min. RAM | 2,048 MB | 2,048 MB |
| Deployment | docker | docker, kubernetes |
| GitHub stars | ★ 18,872 | ★ 7,524 |
| First released | 2015 | 2016 |
| Replaces | Google Workspace, Microsoft 365 | Google Workspace, Microsoft 365 |
What are Docker Mailserver and Mailu?
Docker Mailserver
Docker Mailserver is a single-container mail server built on Postfix and Dovecot with no external database. It is configured entirely through files and environment variables for a reproducible setup.
- Single container, no database
- Postfix and Dovecot core
- SpamAssassin and ClamAV integration
- File-based configuration
Mailu
Mailu is a free mail server distributed as a set of Docker images, providing a complete stack with antispam, webmail, and admin interface. It aims to be simpler and lighter than other mail suites.
- Composable Docker images
- Built-in antispam and antivirus
- Roundcube and SnappyMail webmail
- Admin UI and REST API
Docker Mailserver vs Mailu: key differences
Docker Mailserver is written in Shell, while Mailu is built with Python. Docker Mailserver has the considerably larger community, at 18,872 GitHub stars versus 7,524.
Why pick each one
Choose Docker Mailserver if…
- Reproducible, version-controllable config
- Lightweight
Watch out for
- No built-in webmail
- Requires comfort with mail concepts
Choose Mailu if…
- Lighter than mailcow
- Kubernetes support
Watch out for
- Fewer features than larger suites
- Manual DNS configuration
Frequently asked questions
Is Docker Mailserver or Mailu better?
Neither is universally better. Docker Mailserver has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Docker Mailserver and Mailu free and open-source?
Yes. Docker Mailserver is licensed under MIT and Mailu under MIT. Both can be self-hosted at no software cost.
Can I run Docker Mailserver and Mailu with Docker?
Docker Mailserver: yes. Mailu: yes.