Mailu vs Stalwart Mail Server
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
Not the right match-up?
Mailu
Simple yet full-featured Docker mail server
VS
Stalwart Mail Server
Modern all-in-one mail server in a single binary
| Feature | Mailu | Stalwart Mail Server |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | AGPL-3.0 |
| Language | Python | Rust |
| Setup difficulty | Medium | Medium |
| Min. RAM | 2,048 MB | 512 MB |
| Deployment | docker, kubernetes | docker, binary, bare-metal |
| GitHub stars | ★ 7,443 | ★ 14,059 |
| First released | 2016 | 2020 |
| Replaces | Google Workspace, Microsoft 365 | Microsoft Exchange, Google Workspace |
Why pick each one
Choose Stalwart Mail Server if…
- Single modern binary
- Strong security defaults
Frequently asked questions
Is Mailu or Stalwart Mail Server better?
Neither is universally better. Stalwart Mail Server has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.
Are Mailu and Stalwart Mail Server free and open-source?
Yes. Mailu is licensed under MIT and Stalwart Mail Server under AGPL-3.0. Both can be self-hosted at no software cost.
Can I run Mailu and Stalwart Mail Server with Docker?
Mailu: yes. Stalwart Mail Server: yes.