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Team Chat & Collaboration
Real-time chat, channels, and direct messaging channels.
Trending in Team Chat & Collaboration
Mattermost
Mattermost is an open-source alternative to Slack and Teams that delivers secure team messaging, boards, and incident workflows with self-hosted control.
39.5k+251LinuxmacOSWindowstoday
AGPL-3.0Team Chat & Collaboration
Zulip
Zulip is an open-source team chat platform replacing Slack with organized topic-based threading, rich Markdown support, and self-hosted data control.
26.2k+166LinuxmacOS
Rocket.Chat
Rocket.Chat is an open-source Slack alternative providing self-hosted team messaging, custom TypeScript apps, and complete control over internal data.
46.4k+150LinuxmacOS
Campfire
Self-hosted group chat by 37signals replacing Slack subscriptions with an MIT-licensed, single-container setup powered by SQLite and custom webhooks.
4.8k+141DockerLinux
12 tools found
Rocket.Chat
Rocket.Chat is an open-source Slack alternative providing self-hosted team messaging, custom TypeScript apps, and complete control over internal data.
46.4kLinuxmacOSWindowstoday
MITTeam Chat & Collaboration
Mattermost
Mattermost is an open-source alternative to Slack and Teams that delivers secure team messaging, boards, and incident workflows with self-hosted control.
39.5kLinuxmacOSWindowstoday
AGPL-3.0Team Chat & Collaboration
Zulip
Zulip is an open-source team chat platform replacing Slack with organized topic-based threading, rich Markdown support, and self-hosted data control.
26.2kLinuxmacOSWindows1d ago
Apache-2.0Team Chat & Collaboration
Campfire
Self-hosted group chat by 37signals replacing Slack subscriptions with an MIT-licensed, single-container setup powered by SQLite and custom webhooks.
4.8kDockerLinux1d ago
MITTeam Chat & Collaboration
Cinny
Cinny is an open-source, web-based Matrix chat client offering an intuitive Discord-style interface with end-to-end encryption and total data custody.
4.0kWebtoday
AGPL-3.0Team Chat & Collaboration
Revolt
Revolt is an open-source, self-hosted alternative to Discord that gives teams complete data custody over real-time channels, roles, and voice rooms.
3.4kLinuxmacOSWindows2d ago
AGPL-3.0Team Chat & Collaboration
ES
PromotedEdgar Sipki
Go & gRPC engineer · founder of EasyP
Mentoring for backend developers. Consulting for startups.
Go, gRPC and Protobuf done right, LLM agents in production, and the hard parts of shipping a first product.
GogRPCProtobufLLM agents
sipki.online
Quiet
Quiet is an open-source, peer-to-peer team chat app that replaces Slack with encrypted channels syncing over Tor and IPFS without central servers.
2.7kLinuxmacOSWindows1d ago
GPL-3.0Team Chat & Collaboration
Wire
Wire is an open-source alternative to Slack with default end-to-end encryption for team messaging, voice calls, and secure guest collaboration.
2.6kWeb10mo ago
GPL-3.0Team Chat & Collaboration
Mezon
Mezon is an open-source team chat platform replacing Discord with native desktop speed, end-to-end encryption, and 500MB unmetered file uploads.
2.0kLinuxmacOSWindowstoday
Team Chat & Collaboration
UnInbox
UnInbox is an open-source collaborative email platform that replaces Front with shared inboxes, internal thread notes, and task workflow statuses.
1.8kDockerLinux9mo ago
Team Chat & Collaboration
Ethora
Ethora is an open-source chat SDK platform replacing Sendbird and Stream with Apache-2.0 client libraries and XMPP messaging without per-MAU fees.
552today
Apache-2.0Team Chat & Collaboration
Twake Chat
Twake Chat is an open-source, Matrix-based team chat client that replaces Slack with self-hosted, end-to-end encrypted messaging and data sovereignty.
173DockerLinuxtoday
AGPL-3.0Team Chat & Collaboration