Spark IM vs Zulip
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?
Spark IM
Cross-platform XMPP instant messaging client
VS
Zulip
Threaded team chat that combines email and chat
| Feature | Spark IM | Zulip |
|---|---|---|
| Category | Team Chat | Team Chat |
| License | Apache-2.0 | Apache-2.0 |
| Language | Java | Python |
| Setup difficulty | Easy | Medium |
| Min. RAM | 256 MB | 2,048 MB |
| Deployment | binary, source | docker, bare-metal |
| GitHub stars | ★ 601 | ★ 25,619 |
| First released | 2004 | 2015 |
| Replaces | Slack, Skype | Slack, Microsoft Teams |
Why pick each one
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
Choose Zulip if…
- Excellent conversation organization
- Strong async workflow
- Fully open source
Frequently asked questions
Is Spark IM or Zulip better?
Neither is universally better. Zulip 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 Spark IM and Zulip free and open-source?
Yes. Spark IM is licensed under Apache-2.0 and Zulip under Apache-2.0. Both can be self-hosted at no software cost.
Can I run Spark IM and Zulip with Docker?
Spark IM: check the project docs for container support. Zulip: yes.