SHSelfHostIndex

Cyrus IMAP vs Kolab Groupware

A side-by-side comparison of two self-hosted apps from related categories — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
CY Cyrus IMAP Scalable IMAP and POP server for large deployments VS KO Kolab Groupware Open-source groupware server with mail and calendaring
FeatureCyrus IMAPKolab Groupware
CategoryMail ServersGroupware
LicenseBSD-3-ClauseAGPL-3.0
LanguageCPHP
Setup difficultyHardHard
Min. RAM1,024 MB2,048 MB
Deploymentbare-metal, sourcebare-metal, docker
GitHub stars★ 641★ 200
First released19942002
ReplacesMicrosoft ExchangeMicrosoft Exchange, Zimbra

Why pick each one

Choose Cyrus IMAP if…

  • Released under the BSD-3-Clause license
  • Written in C
Cyrus IMAP details

Choose Kolab Groupware if…

  • Built on proven components
  • Strong standards support
Kolab Groupware details

Frequently asked questions

Is Cyrus IMAP or Kolab Groupware better?

Neither is universally better. Cyrus IMAP has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.

Are Cyrus IMAP and Kolab Groupware free and open-source?

Yes. Cyrus IMAP is licensed under BSD-3-Clause and Kolab Groupware under AGPL-3.0. Both can be self-hosted at no software cost.

Can I run Cyrus IMAP and Kolab Groupware with Docker?

Cyrus IMAP: check the project docs for container support. Kolab Groupware: yes.

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