Chatmail 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?
Chatmail
Minimal, instant-onboarding mail server for Delta Chat
VS
Stalwart Mail Server
Modern all-in-one mail server in a single binary
| Feature | Chatmail | Stalwart Mail Server |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MPL-2.0 | AGPL-3.0 |
| Language | Python | Rust |
| Setup difficulty | Medium | Medium |
| Min. RAM | 512 MB | 512 MB |
| Deployment | docker, bare-metal, source | docker, binary, bare-metal |
| GitHub stars | ★ 476 | ★ 14,059 |
| First released | 2023 | 2020 |
| Replaces | Microsoft Exchange, Google Workspace |
Why pick each one
Choose Chatmail if…
- Released under the MPL-2.0 license
- First-class Docker support for quick deployment
- Written in Python
- Lightweight — runs in 512 MB RAM
Choose Stalwart Mail Server if…
- Single modern binary
- Strong security defaults
Frequently asked questions
Is Chatmail 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 Chatmail and Stalwart Mail Server free and open-source?
Yes. Chatmail is licensed under MPL-2.0 and Stalwart Mail Server under AGPL-3.0. Both can be self-hosted at no software cost.
Can I run Chatmail and Stalwart Mail Server with Docker?
Chatmail: yes. Stalwart Mail Server: yes.