Self-hosted Team Chat & Messaging tools

Rocket.Chat is an open-source communications platform for secure team messaging, channels, DMs, voice/video, integrations, and customer omnichannel support.

Actively maintained

Alternative to:

Rocket.Chat Cloud+19

Novu is an open-source notifications platform with a unified API, workflow orchestration, and embeddable in-app inbox for email, SMS, push, and chat.

Actively maintained

Alternative to:

Novu Cloud+4

Open-source, self-hosted messaging platform for secure team collaboration with real-time chat, audio calls, screen sharing, and integrations.

Actively maintained

Alternative to:

Slack+19

Chatwoot is an open-source customer support platform with a shared inbox for live chat, email, and messaging channels, plus automation, reporting, and a help center.

Actively maintained

Alternative to:

Intercom+19

ntfy is a lightweight HTTP pub-sub service to send push notifications to phones, desktops, and browsers via PUT/POST or a REST API.

Apache-2.0Actively maintained

Alternative to:

Pushover+8

Huly is an open-source all-in-one platform combining project management, team chat, and collaborative documentation as an alternative to tools like Jira, Linear, Slack, and Notion.

EPL-2.0Actively maintained

Alternative to:

Linear+19

Open-source team chat server with topic-based threading for focused, asynchronous, and real-time communication in distributed teams.

Apache-2.0Actively maintained

Alternative to:

Zulip Cloud+19

Open-source, decentralized messaging network built on a Haskell core with Kotlin Multiplatform and native iOS clients; end-to-end encrypted messaging without user IDs.

AGPL-3.0Actively maintained

Alternative to:

Signal+11

Gotify is a self-hosted notification server that delivers messages in real time via WebSocket, with a REST API, web UI, and optional clients like Android and CLI.

Habitica is an open-source gamified task manager turning Habits, Dailies, and To-Dos into RPG quests with avatars, gear and social features.

Actively maintained

Alternative to:

Habitica+15

Tinode is an open source instant messaging platform with a Go backend, web/mobile clients, JSON WebSocket and gRPC APIs, and support for one-to-one and group chat.

GPL-3.0Actively maintained

Alternative to:

Telegram+13

Element is a Matrix client for secure team messaging and collaboration, offering end-to-end encrypted chats and calls with interoperability across the Matrix network.

AGPL-3.0Actively maintained

Alternative to:

Element Matrix (Hosted)+19

Owncast is a self-hosted live streaming server that supports RTMP ingest, HLS playback, and built-in web chat, with optional Fediverse (ActivityPub) integration.

MITActively maintained

Alternative to:

YouTube+12

ejabberd is an Erlang/OTP-based messaging server providing XMPP chat and presence, MQTT broker capabilities for IoT, and SIP services for real-time communications.

Actively maintained

Alternative to:

CloudMQTT+11

Spacebar is an open source, self-hostable Discord-compatible communication platform with text chat, voice, and video, designed to work with existing clients and bots.

AGPL-3.0Actively maintained

Alternative to:

Discord+19

Self-hosted web-based IRC client with multi-user support, persistent connections, and a responsive UI for desktop and mobile.

MITActively maintained

Alternative to:

The Lounge Cloud+3

Open-source, local-first Slack and Notion alternative combining team chat, rich docs, databases, and file management with offline-first sync and self-hosting.

Apache-2.0Actively maintained

Alternative to:

Notion+19

Synapse is a Matrix homeserver implementation for running federated, secure real-time chat and collaboration on your own infrastructure.

AGPL-3.0Actively maintained

Alternative to:

Element Matrix (Hosted)+19

Tailchat is an open source team chat and collaboration platform with a strong plugin system, bot integrations, multi-group workspaces, and RBAC permissions.

Apache-2.0Actively maintained

Alternative to:

Slack+14

Converse.js is an open-source, client-side web XMPP/Jabber chat app that can run standalone or be embedded into sites, with group chat and OMEMO encryption.

MPL-2.0Actively maintained

Alternative to:

IRCCloud+19

Ergo is a modern IRC server (ircd) written in Go, with integrated account management, history storage, bouncer-like features, and strong IRCv3 support.

MITActively maintained

Alternative to:

IRCCloud+12

Stoat is an open-source, self-hostable chat platform for communities and teams, offering text channels, permissions, moderation tools, and a web app.

Actively maintained

Alternative to:

Discord+13

Openfire is an open source XMPP (Jabber) server for real-time messaging and collaboration, with a web admin console and a plugin ecosystem.

Apache-2.0Actively maintained

Alternative to:

Cisco Jabber+15

Tox is a decentralized, peer-to-peer communication system for encrypted messaging, voice/video calls, screen sharing, and file transfers without central servers.

GPL-3.0Actively maintained

Alternative to:

Signal+12

Stoat (formerly Revolt) is an open-source chat platform for communities and teams with channels, direct messages, roles/permissions, moderation tools, and bot support.

AGPL-3.0Actively maintained

Alternative to:

Discord+11

Open-source browser-based peer-to-peer chat with E2E encryption, ephemeral messages, video/audio, screen sharing, direct file transfer, and iframe embedding.

GPL-2.0Actively maintained

Alternative to:

Zoom+15

Self-hosted live chat and customer support platform with website widgets, operator console, chatbots, omnichannel integrations, and optional voice/video/screensharing.

Apache-2.0Actively maintained

Alternative to:

Zendesk+19

ZNC is an advanced IRC bouncer that stays connected to IRC networks, letting you reconnect from one or more clients and replay buffered messages you missed.

Apache-2.0Actively maintained

Alternative to:

IRCCloud+3

Movim is a federated social platform and web-based XMPP client for blogging, chat, communities, and real-time messaging with a responsive cross‑platform interface.

AGPL-3.0Actively maintained

Alternative to:

Element Matrix (Hosted)+15

RetroShare is a decentralized friend-to-friend platform for encrypted chat, mail, forums, channels and secure file sharing, with optional Tor/I2P support.

Actively maintained

Alternative to:

Telegram+19