Self-hosted team chat with the features people actually use in Slack: channels, threads, search and integrations. Rocket.Chat is the direct swap with bridges to other networks; Element (on the Synapse server) uses the open Matrix protocol with end-to-end encryption; Mumble stays the lightweight classic for voice.
Open source alternatives to Slack
Self-hosted team chat with the features people actually use in Slack: channels, threads, search and integrations. Rocket.Chat is the direct…
Compare
| Program | License | Self-hosted | Last release | Activity |
|---|---|---|---|---|
| Rocket.Chat | — | Yes | Oct 5, 2026 | Nov 2026 |
| Element | AGPL-3.0 | Yes | Oct 27, 2026 | Nov 2026 |
| Synapse | — | Yes | — | — |
| Mumble | — | Yes | — | — |
| Tuwunel | Apache-2.0 | Yes | Oct 10, 2026 | Nov 2026 |
| Continuwuity | Apache-2.0 | Yes | Aug 7, 2026 | Nov 2026 |
| Conduit | Apache-2.0 | Yes | Sep 29, 2026 | Nov 2026 |
| Jami | MIT | Yes | — | Oct 2020 |
| Tox | GPL-3.0 | Yes | Mar 12, 2015 | Jul 2024 |
| RetroShare | — | Yes | Nov 30, 2023 | Nov 2026 |
Rocket.Chat
v8.9.0
★ 46,372
Element
v1.12.33
★ 13,642
Synapse
Mumble
Tuwunel
v1.9.4
★ 2,735
Continuwuity
v26.7.2
★ 1,160
Conduit
★ 603
Jami
★ 28
Tox
★ 8,743
RetroShare
v0.6.7.2
★ 2,027
How to choose
Compare the options on what matters for your case: the license (if you run a business, check commercial use), the platforms you already operate, and how actively each project releases. Every program above links to its official project page, release notes and source code.
Questions
Can we keep talking to Slack users?
Rocket.Chat and Element both have bridges to Slack and other networks.