Zulip for open source.

Grow your community with fun, thoughtful, and inclusive discussion.

Zulip Standard is free for open-source projects! Contact sales@zulip.com to check whether your organization qualifies, or request sponsorship today.

Below, we’ve collected a list of Zulip features that are particularly useful to open source communities. We also recommend checking out Zulip for communities to learn how Zulip empowers welcoming communities by making it easy to participate on your own time.



Moderation suite.

Moderation is a big part of making an open community work. Zulip was built for open communities from the beginning and comes with moderation tools out of the box.

Open invitations.

Allow anyone to join without an invitation. You can also link to your Zulip with a badge in your readme document.

Authenticate with GitHub or GitLab.

Allow (or require) users to authenticate with their GitHub or GitLab account, instead of with a username and password.

Import from Slack, Mattermost, Gitter, or Rocket.Chat.

Import your existing organization from Slack, Mattermost, Gitter, or Rocket.Chat.



Collaborate on code and formulas

Markdown code blocks with syntax highlighting make it easy to discuss code, paste an error message, or explain a complicated point. Native LaTeX support provides the same benefits when talking about math.

You can also instantly copy a code block to your clipboard or transfer it to an external code playground to interactively run and debug the code.

If your community primarily uses a single programming language, consider setting a default code block language.

Zulip makes it easy to get a permanent link to a conversation, which you can use in your issue tracker, forum, or anywhere else. Zulip’s topic-based threading helps keep conversations coherent and organized so they are useful for posterity.

Efficiently refer to issues or code reviews with notation like #1234 or T1234. You can set up any regex as a custom linkification filter for your organization.

Hundreds of integrations.

Get events from GitHub, Travis CI, Jira, and hundreds of other tools right in Zulip. Topics give each issue its own place for discussion.

“Wikimedia uses Zulip for its participation in open source mentoring programs. Zulip’s threaded discussions help busy organization administrators and mentors stay in close communication with students during all phases of the programs.”

— Srishti Sethi, Developer Advocate, Wikimedia Foundation

Mirror IRC, Matrix, or Slack.

Two-way integrations with IRC, Matrix, and/or Slack using Matterbridge.

Scales to 10,000s of members.

Zulip is designed to perform well in common use cases for open source projects, with features like soft deactivation to make message delivery efficient even when sending to a stream with 10,000s of inactive subscribers.

Full-text search of all public history.

Zulip’s full-text search supports searching the organization’s entire public history via the streams:public search operator, allowing Zulip to provide all the benefits of a searchable project forum.

Public archive.

Allow search engines to index your chat, with a read-only view of your public streams. Zulip’s topic-based threading keeps conversations coherent and organized, enabling a meaningful archive indexed by search engines.

Currently implemented as an out-of-tree tool, though a native feature built into the Zulip server is coming soon.

Logged-out public access (coming soon).

Coming soon: Allow users to read and search public stream history in Zulip’s UI without first creating an account.

Quality data export.

Our high quality export and import tools ensure you can always move from Zulip Cloud hosting to your own servers.

Free and open source.

Unlike many modern "open source" applications that are actually Open Core, Zulip is 100% Free and Open Source software. All code, including for the server, desktop, mobile, and beta terminal apps is available under the Apache 2 license.

We love helping other open source communities and prioritize feature requests from open source communities the same way we prioritize feature requests from paying customers.

So if there’s something we could improve to make Zulip the obvious choice either for you or your community, contact us and we'll do what we can to help!

“I highly recommend Zulip to other communities. We’re coming from Freenode as our only real-time communication so the difference is night and day. Slack is a no-go for many due to not being FLOSS, and I’m concerned about vendor lock-in if they were to stop being so generous. Slack’s threading model is much worse than Zulip’s IMO. The streams/topics flow is an incredibly intuitive way to keep track of everything that is going on.”

— RJ Ryan, Mixxx Developer

Zulip Standard is free for open-source projects!

Join the hundreds of open-source projects we sponsor.


Leading open source projects use Zulip: