Apache James vs WildDuck
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | Apache James | WildDuck |
|---|---|---|
| Deploy effort | Under-an-hour setup | Under-an-hour setup |
| Health score | 78 · Good | 86 · Excellent |
| Category | Mail Servers | Mail Servers |
| License | Apache-2.0 | EUPL-1.2 |
| Language | Java | JavaScript |
| Setup difficulty | Hard | Hard |
| Min. RAM | 2,048 MB | 1,024 MB |
| Deployment | docker, source | docker, bare-metal |
| GitHub stars | ★ 1,044 | ★ 2,108 |
| First released | 2003 | 2017 |
| Replaces | Microsoft Exchange | Microsoft Exchange, Gmail |
What are Apache James and WildDuck?
Apache James
Apache James is a complete enterprise mail server and SMTP, IMAP, and POP3 platform from the Apache Foundation. It can be fully self-hosted and extended with custom mailets for processing mail.
- Enterprise mail server platform
- SMTP, IMAP, and POP3 support
- Extensible with custom mailets
WildDuck
WildDuck is a modern, scalable mail server providing IMAP, POP3, and a full REST API for managing mailboxes. It stores messages in MongoDB and is designed for clustered, highly available deployments.
- IMAP and POP3
- Full REST API
- MongoDB storage
- Designed for scale
Apache James vs WildDuck: key differences
Apache James is written in Java, while WildDuck is built with JavaScript. Licensing differs — Apache-2.0 for Apache James versus EUPL-1.2 for WildDuck. WildDuck is the lighter option, starting around 1,024 MB of RAM against 2,048 MB for Apache James. Apache James is the more established project (first released 2003), while WildDuck arrived in 2017. WildDuck has the considerably larger community, at 2,108 GitHub stars versus 1,044.
Why pick each one
Choose Apache James if…
- Released under the Apache-2.0 license
- First-class Docker support for quick deployment
- Active community (1k GitHub stars)
- Written in Java
Choose WildDuck if…
- API-driven management
- Horizontally scalable
Watch out for
- Requires MongoDB
- Complex to operate
Frequently asked questions
Is Apache James or WildDuck better?
Neither is universally better. WildDuck has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.
Are Apache James and WildDuck free and open-source?
Yes. Apache James is licensed under Apache-2.0 and WildDuck under EUPL-1.2. Both can be self-hosted at no software cost.
Can I run Apache James and WildDuck with Docker?
Apache James: yes. WildDuck: yes.
Which is lighter on resources, Apache James or WildDuck?
WildDuck has the smaller minimum footprint at 1,024 MB of RAM, compared to about 2,048 MB for Apache James. Real-world usage depends on library size, user count, and enabled features.