HyperKitty vs Schleuder
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | HyperKitty | Schleuder |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Category | Mail Servers | Mail Servers |
| License | GPL-3.0 | GPL-3.0 |
| Language | Python | Ruby |
| Setup difficulty | Hard | Hard |
| Min. RAM | 1,024 MB | 256 MB |
| Deployment | docker, source | bare-metal, source |
| GitHub stars | ★ 200 | ★ 100 |
| First released | 2014 | 2009 |
| Replaces | Google Groups | Google Groups |
What are HyperKitty and Schleuder?
HyperKitty
HyperKitty is the official web-based archiver and interface for Mailman 3, presenting mailing-list discussions as browsable, searchable threads. It allows reading and replying to list traffic from a browser.
- Web archive for Mailman 3
- Threaded list browsing
- Full-text search
- Reply from the browser
Schleuder
Schleuder is a mailing list manager designed for groups that need encrypted communication, decrypting incoming and re-encrypting outgoing mail with OpenPGP. It also serves as a remailer for confidential teams.
- OpenPGP encrypted lists
- Re-encrypts for each member
- Remailer functionality
- Key management
HyperKitty vs Schleuder: key differences
HyperKitty is written in Python, while Schleuder is built with Ruby. Schleuder is the lighter option, starting around 256 MB of RAM against 1,024 MB for HyperKitty. Schleuder is the more established project (first released 2009), while HyperKitty arrived in 2014. HyperKitty has the considerably larger community, at 200 GitHub stars versus 100. HyperKitty lists first-class Docker deployment; Schleuder does not.
Why pick each one
Choose HyperKitty if…
- Released under the GPL-3.0 license
- First-class Docker support for quick deployment
- Written in Python
Choose Schleuder if…
- Released under the GPL-3.0 license
- Written in Ruby
- Tiny footprint — runs in 256 MB RAM
Frequently asked questions
Is HyperKitty or Schleuder better?
Neither is universally better. HyperKitty has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.
Are HyperKitty and Schleuder free and open-source?
Yes. HyperKitty is licensed under GPL-3.0 and Schleuder under GPL-3.0. Both can be self-hosted at no software cost.
Can I run HyperKitty and Schleuder with Docker?
HyperKitty: yes. Schleuder: check the project docs for container support.
Which is lighter on resources, HyperKitty or Schleuder?
Schleuder has the smaller minimum footprint at 256 MB of RAM, compared to about 1,024 MB for HyperKitty. Real-world usage depends on library size, user count, and enabled features.