Citadel vs WildDuck
A side-by-side comparison of two self-hosted apps from related categories — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Citadel
All-in-one groupware, mail and collaboration server
VS
WildDuck
Scalable IMAP and POP3 mail server with REST API
| Feature | Citadel | WildDuck |
|---|---|---|
| Category | Groupware | Mail Servers |
| License | GPL-3.0 | EUPL-1.2 |
| Language | C | JavaScript |
| Setup difficulty | Medium | Hard |
| Min. RAM | 512 MB | 1,024 MB |
| Deployment | bare-metal, source | docker, bare-metal |
| GitHub stars | ★ 100 | ★ 2,107 |
| First released | 1987 | 2017 |
| Replaces | Microsoft Exchange, Microsoft 365 | Microsoft Exchange, Gmail |
Why pick each one
Frequently asked questions
Is Citadel or WildDuck better?
Neither is universally better. WildDuck has the larger community, while Citadel is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.
Are Citadel and WildDuck free and open-source?
Yes. Citadel is licensed under GPL-3.0 and WildDuck under EUPL-1.2. Both can be self-hosted at no software cost.
Can I run Citadel and WildDuck with Docker?
Citadel: check the project docs for container support. WildDuck: yes.