Mattermost vs Spark IM

A side-by-side comparison of two self-hosted team chat options — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
FeatureMattermostSpark IM
CategoryTeam ChatTeam Chat
LicenseAGPL-3.0Apache-2.0
LanguageTypeScriptJava
Setup difficultyMediumEasy
Min. RAM2,048 MB256 MB
Deploymentdocker, bare-metal, kubernetesbinary, source
GitHub stars★ 38,708★ 601
First released20162004
ReplacesSlack, Microsoft TeamsSlack, Skype

Why pick each one

Choose Mattermost if…

  • Great for technical teams
  • Strong security posture
  • Good integrations
Mattermost details

Choose Spark IM if…

  • Released under the Apache-2.0 license
  • Easy to set up — beginner-friendly
  • Written in Java
  • Tiny footprint — runs in 256 MB RAM
Spark IM details

Frequently asked questions

Is Mattermost or Spark IM better?

Neither is universally better. Mattermost has the larger community, while Spark IM is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.

Are Mattermost and Spark IM free and open-source?

Yes. Mattermost is licensed under AGPL-3.0 and Spark IM under Apache-2.0. Both can be self-hosted at no software cost.

Can I run Mattermost and Spark IM with Docker?

Mattermost: yes. Spark IM: check the project docs for container support.

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