There are many alternatives to Slack for Linux if you are looking for a replacement. The best open source Linux alternative is Element. It's not free, so if you're looking for a free alternative, you could try Element or Zulip. If that doesn't suit you, our users have ranked more than 100 alternatives to Slack and many of them are open source and available for Linux so hopefully you can find a suitable replacement. Other interesting open source Linux alternatives to Slack are Matrix, Wire, Stoat Chat and Threema.
Provides secure collaboration with end-to-end encryption, supporting chat, voice, and video calls. Available on all major platforms, it enables digital sovereignty with a decentralized design and interoperability through bridges to systems like Slack and Teams. Includes enterprise-grade SaaS.
Threaded group conversations combine live and asynchronous messaging, separating topics for organized collaboration, supporting open-source, cloud, and self-hosted deployments, secure communication with encryption, and multi-platform access for diverse teams.
Open-source chat server supporting real-time group, direct, and private messaging, video calls, file sharing, helpdesk chat, API integrations, desktop notifications, emojis, LDAP authentication, cross-platform apps, and customizable extensions for teams.
Open standard protocol enabling decentralized, encrypted instant messaging, VoIP signaling, IoT device connectivity, and persistent data management across federated servers without central control or single points of failure, bridging communication platforms.
Secure communication platform featuring encrypted chats and calls, file and media sharing, self-deleting messages, device verification, group collaboration, and customizable settings. Supports use across multiple devices with no phone number required for access.
Instant messaging platform supporting text and voice channels, live video calls, secure screen sharing, private group chats, customizable permissions, moderation tools, bot integration, privacy-focused design, open-source development, and cross-platform use.
Threema is a new mobile messaging app that puts security first. With true end-to-end encryption, you can rest assured that only you and the intended recipient can read your messages.
Peer-to-peer group chatting over Tor and IPFS, with local-first encrypted messaging and no central servers, offers privacy-focused decentralized collaboration for teams, supporting desktop and mobile. FOSS, open to contributors, and avoids surveillance-based tracking.
Twake is a real-time teamwork platform. It is a suite of collaborative tools that includes the specificities of some bestsellers (Slack, Trello, Google Drive...). We provide professional messaging, storage space, online collaborative editors (Words, Excel, PowerPoint), task...
Self-hosted communication platform with secure audio, video, chat, web conferencing, screensharing, advanced encryption, and metadata privacy, running on user-controlled servers, supporting web and mobile apps, and eliminating third-party data exposure.
The best Discord alternative. Mezon is a Live, Work, and Play platform. It’s perfect for gaming and chilling with friends, or even building a global community. Customize your own space to talk, play, and hang out.
Open-source chat platform providing community-focused group messaging, video calls, profile customization with animated avatars, custom emojis, tags, post creation, discovery of communities, and full source code access on GitHub. Entirely donation-funded.
![Profile Interface [PC - 2025]](https://img.alternativeto.net/s/618x394/avif/nerimity_993222_full.png)
![Messages View [PC - 2025]](https://img.alternativeto.net/s/618x394/avif/nerimity_281418_full.png)
![Server Discovery [PC - 2025]](https://img.alternativeto.net/s/618x394/avif/nerimity_282508_full.png)
![Server Settings [PC - 2025]](https://img.alternativeto.net/s/618x394/avif/nerimity_628028_full.png)
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because its open source, decentralised, and end-to-end secure. Plus the folks at matrix.org are working to get us out of our communication silos by creating standards for communication interoperability!