Open Source Slack Alternatives

    The best open source alternative to Slack is Mattermost, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Slack and many of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Slack are Element (Free Personal, Open Source), Zulip (Free Personal, Open Source), Rocket.Chat (Freemium, Open Source) and Matrix.org (Free, Open Source).

    This page was last updated Jun 11, 2021

    1. Librem Chat – end-to-end encrypted chat, VOIP, and video calling used by millions of people * Chat rooms * Share images, videos, and files * Make voice and video calls * Keep your conversations secret with end-to-end encryption * Free and open-source software
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    2. kune is a social network where you can communicate, collaborate and share between equals, using different web tools: documents, calendars, chats, wiki, messages, tasks, forums, barters.
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      kune vs Slack opinions
      pros, cons and recent comments
      Danilo_Venom Like Slack, it offers group communication and collaboration, task and document management
      Positive comment over 4 years ago

      0


      • FreeOpen Source
      • Online
      • Android
      • Self-Hosted
      hack.chat is a minimal, distraction-free chat application.
      Channels are created and joined by going to https://hack.chat/?your-channel. There are no channel lists, so a secret channel name can be used for private discussions.

      Source code : https://github.com/hack-chat/main
      • FreeOpen Source
      • Mac
      • Windows
      • Linux
      • Online
      • Android
      • iPhone
      • Chrome OS
      • Self-Hosted
      Dirc is a peer-to-peer web application which uses WebRTC to set up connections between chat participants without requiring a back-end server. The static files can be self-hosted. Other features: * Identities are key pairs (NaCl).
      • FreeOpen Source
      • Mac
      • Linux
      • Amazon Web Services
      • Microsoft Azure
      MongooseIM is aimed at large, complex enterprise level projects, where real-time communication is critical for business success. It provides high availability, ease of deployment, development and reliability in production.
      No screenshots yet


      • FreemiumOpen Source
      • Self-Hosted
      • total.js
      • Node.JS
      Total.js Messenger is a small alternative to Slack built on Node.js and total.js .
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      • FreeOpen Source
      • Mac
      • Windows
      • Linux
      • Self-Hosted
      No servers are needed to join a cabal, or to start your own. Everything is stored and runs locally. A cabal can never go down or be taken away.
      No screenshots yet
      • FreeOpen Source
      • Mac
      • Windows
      • Linux
      • Online
      • Android
      • Android Tablet
      • Self-Hosted
      • Google Chrome
      • WeeChat
      • Firefox OS
      • Google Play Store
      • Firefox
      Glowing Bear is a sleek, modern web frontend that securely connects to a running instance of WeeChat using its built-in relay protocol.
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    3. Communication is critical. Privacy is essential. Simple, just how you like it. Revolt is built on the same technologies as other popular chat applications, so there won’t be any need to re-learn on how to use it. Also, you can customize it to your heart’s content.
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    4. AtomJump.com is a well tuned hosted version of the free open-source AtomJump.org. It is free to chat publicly with your family, group or co-workers on your own group.
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    Showing 30 of 42 alternatives