Zulip

Zulip is a powerful, open source group chat application.

★ Stars26.1k26,050 on GitHub

Last commit5 days ago14 Oct 2026

LicenceApache-2.0SPDX, from the repository

From GitHub via awesome-selfhosted-data, as of 17 Oct 2026.

Zulip is a powerful, open source group chat application.

Who it suits

Distributed teams: Zulip is “organized chat for distributed teams”, “designed for async conversations”.
2 GB RAM minimum; 4 GB for 100+ users.

Your data: Slack exports public channel history as a zip; Zulip imports it along with users and custom emoji.

Make sure you're an owner or admin of the Slack workspace.
Export your Slack message history; the zip is usually ready a few minutes after you start.
Export user data and custom emoji as well.
Import the export into your Zulip server following Zulip's Slack import guide, then decide how users will log in.

Watch out for:

Slack only lets Business+ and Enterprise Grid workspaces export private channels and direct messages.

Runs with	Python
ARM / Raspberry Pi	Yes Supported CPU architectures: x86-64 and aarch64.
Memory (RAM)	2 GB minimum; 4 GB for 100+ users Under 5 GB of RAM, Zulip requires swap (2 GB recommended).

Sources: zulip.readthedocs.io/en/latest/production/requirements.html, checked 19 Oct 2026. “Runs with” is from this listing. Blank means we haven't found it in official docs yet, not that it's unsupported.

Status	Open source
Licence	Apache-2.0
Platforms	Python
Category	Communication - Custom Communication Systems
Website	zulip.org
Source	GitHub

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