Haraka vs RainLoop
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?
Haraka
High-performance, pluggable SMTP server in Node.js
VS
RainLoop
Simple, modern and fast web-based email client
| Feature | Haraka | RainLoop |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | AGPL-3.0 |
| Language | JavaScript | PHP |
| Setup difficulty | Medium | Easy |
| Min. RAM | 256 MB | 128 MB |
| Deployment | docker, bare-metal, source | docker, bare-metal, source |
| GitHub stars | ★ 5,612 | ★ 4,120 |
| First released | 2011 | 2013 |
| Replaces | SendGrid, Mailgun | Gmail, Outlook Web |
Why pick each one
Choose RainLoop if…
- Released under the AGPL-3.0 license
- Easy to set up — beginner-friendly
- First-class Docker support for quick deployment
- Active community (4.1k GitHub stars)
Frequently asked questions
Is Haraka or RainLoop better?
Neither is universally better. Haraka has the larger community, while RainLoop is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.
Are Haraka and RainLoop free and open-source?
Yes. Haraka is licensed under MIT and RainLoop under AGPL-3.0. Both can be self-hosted at no software cost.
Can I run Haraka and RainLoop with Docker?
Haraka: yes. RainLoop: yes.