Postal vs fdm
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?
Postal
Complete mail delivery platform for outgoing email
VS
fdm
Fetch and filter mail with a single configuration
| Feature | Postal | fdm |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | ISC |
| Language | Ruby | C |
| Setup difficulty | Hard | Medium |
| Min. RAM | 2,048 MB | 32 MB |
| Deployment | docker, bare-metal | binary, source |
| GitHub stars | ★ 16,724 | ★ 283 |
| First released | 2017 | 2006 |
| Replaces | SendGrid, Mailgun, Postmark | fetchmail, procmail |
Why pick each one
Choose fdm if…
- Released under the ISC license
- Written in C
- Tiny footprint — runs in 32 MB RAM
Frequently asked questions
Is Postal or fdm better?
Neither is universally better. Postal has the larger community, while fdm is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.
Are Postal and fdm free and open-source?
Yes. Postal is licensed under MIT and fdm under ISC. Both can be self-hosted at no software cost.
Can I run Postal and fdm with Docker?
Postal: yes. fdm: check the project docs for container support.