No direct Viva Engage replacements listed yet
Open-source team chat tools. To compare with Viva Engage.
60 open-source team chat tools
Rocket.Chat
Team Chat
The Secure CommsOS™ for mission-critical operations
OSSvs Slack★ 46k
Mattermost
Team Chat
Mattermost is an open source platform for secure collaboration across the entire software
OSSvs Slack★ 39k
Telegram Desktop
Team Chat
Telegram Desktop messaging app
GPL-3.0vs WhatsApp★ 33kTelegram for Android
Team Chat
Telegram for Android source
GPL-2.0vs WhatsApp★ 30k
Signal Android
Team Chat
A private messenger for Android.
AGPL-3.0vs WhatsApp★ 29k
Zulip
Team Chat
Zulip server and web application. Open-source team chat that helps teams stay productive a
Apache-2.0vs Slack★ 26k
SimpleX Chat
Team Chat
SimpleX - the first messaging network operating without user identifiers of any kind - 100
AGPL-3.0vs WhatsApp★ 20k
OpenIM
Backend as a Service
IM Chat OpenClaw
Apache-2.0vs Sendbird★ 17k
Signal Desktop
Team Chat
A private messenger for Windows, macOS, and Linux.
AGPL-3.0vs WhatsApp★ 17k
Element
Team Chat
A glossy Matrix collaboration client for the web.
AGPL-3.0vs Slack★ 14k
Signal iOS
Team Chat
A private messenger for iOS.
AGPL-3.0vs WhatsApp★ 12k
Signal Server
Team Chat
Server supporting the Signal Private Messenger applications on Android, Desktop, and iOS
AGPL-3.0vs WhatsApp★ 11k
Mumble
Team Chat
Mumble is an open-source, low-latency, high quality voice chat software.
OSSvs Discord★ 8.3k
ejabberd
Team Chat
Robust, Ubiquitous and Massively Scalable Messaging Platform (XMPP, MQTT, SIP Server)
OSS★ 6.7k
The Lounge
Team Chat
💬 Modern, responsive, cross-platform, self-hosted web IRC client
MIT★ 6.3k
Campfire
Team Chat
Super simple group chat, without a subscription
MITvs Slack★ 4.7k
Ferdium
Productivity
All your services in one place, built by the community
Apache-2.0vs Beeper★ 4.6k
Synapse
Team Chat
Synapse: Matrix homeserver written in Python/Twisted + Rust
AGPL-3.0vs Slack★ 4.7k
Macro
Productivity
Macro is a unified workspace for teams: email, chat, docs, tasks, agents, calls, and CRM —
AGPL-3.0vs Slack★ 4.5k
Cinny
Team Chat
Yet another matrix client
AGPL-3.0vs Slack★ 3.9k
Element Android
Team Chat
A Matrix collaboration client for Android.
AGPL-3.0vs Slack★ 3.7k
Asterisk
Team Chat
The official Asterisk Project repository.
OSSvs RingCentral★ 3.6k
JuggleIM
Backend as a Service
IM Chat, High-performance, scalable, self-hosted instant messaging server in Go — private
Apache-2.0vs Sendbird★ 3.5k
Stoat
Team Chat
The software powering Stoat
OSSvs Discord★ 3.4k
WeeChat
Team Chat
The extensible chat client.
GPL-3.0★ 3.4k
Converse.js
Team Chat
Web-based XMPP/Jabber chat written in JavaScript
MPL-2.0★ 3.3k
FluffyChat
Team Chat
The cutest instant messenger in the [matrix]
AGPL-3.0vs WhatsApp★ 3.2k
Openfire
Team Chat
An XMPP server licensed under the Open Source Apache License.
Apache-2.0vs Slack★ 3.1k
Chatto
Team Chat
A fully-featured team and group chat application that you can easily selfhost.
AGPL-3.0vs Slack★ 2.8k
Wildfire Chat Android
Team Chat
即时通讯，聊天，野火IM Android客户端，支持Android 4.x —— 最新
OSSvs WeChat★ 2.7k
Wire
Team Chat
🇪🇺 Wire back-end services
AGPL-3.0vs Slack★ 2.8k
Quiet
Team Chat
A private, p2p alternative to Slack and Discord built on Tor & IPFS
GPL-3.0vs Slack★ 2.7k
Tuwunel
Team Chat
Official successor to conduwuit
Apache-2.0vs Slack★ 2.6kWebChat
Team Chat
💬 Chat with anyone on any website.
MIT★ 2.6k
Nheko
Team Chat
Desktop client for Matrix using Qt and C++20.
GPL-3.0vs Slack★ 2.5k
Rocket.Chat Mobile
Team Chat
The Secure CommsOS™ for mission-critical operations
MITvs Slack★ 2.4k
Chitchatter
Team Chat
Secure peer-to-peer chat that is serverless, decentralized, and ephemeral
GPL-2.0vs Whereby★ 2.3k
VoceChat
Team Chat
VoceChat Web App
GPL-3.0vs Slack★ 2.3k
Movim
Team Chat
Movim - Decentralized social platform
AGPL-3.0★ 2.1k
Mezon
Team Chat
Mezon is a new way to communicate with your team. It's faster, better organized, better fo
OSSvs Slack★ 2k
MongooseIM
Team Chat
MongooseIM is Erlang Solutions' robust, scalable and efficient XMPP server, aimed at large
OSS★ 1.8k
Rocket.Chat Desktop
Team Chat
The Secure CommsOS™ for mission-critical operations
MITvs Slack★ 1.7k
Delta Chat
Team Chat
Decentralized private messenger with chat-shared tools and games for Desktop
GPL-3.0vs WhatsApp★ 1.6kOpen OSCAR Server
Team Chat
Self-hostable instant messaging server compatible with classic AIM and ICQ clients written
MIT★ 1.6k
Sharkord
Team Chat
Lightweight, self-hosted, open-source chat server with voice, video, text, and screen shar
MITvs Discord★ 1.5k
hack.chat
Team Chat
a minimal, distraction-free chat application
OSS★ 1.4k
Errbot
Workflow Automation
Errbot is a chatbot, a daemon that connects to your favorite chat service and bring your t
GPL-3.0★ 3.3k
Wildfire IM
Team Chat
即时通讯，聊天，野火IM iOS客户端
OSSvs WeChat★ 1.2k
Convos
Team Chat
Convos :busts_in_silhouette: is the simplest way to use IRC in your browser
Artistic-2.0★ 1.2k
ZapFast
Team Chat
ZapFast: a fast, native WhatsApp client in Rust and egui
MITvs WhatsApp★ 1.2k
Gochat
Team Chat
goim server write by golang !🚀
MIT★ 2.9k
Continuwuity
Team Chat
[Mirror] Continuwuity, the official community driven continuation of conduwuit & Con
Apache-2.0★ 1.1k
FusionPBX
Team Chat
Official FusionPBX - A full-featured domain based multi-tenant PBX and voice switch for Fr
OSSvs RingCentral★ 1.1k
Dino
Team Chat
Modern XMPP ("Jabber") Chat Client using GTK/Vala
GPL-3.0★ 2.5k
Zulip Desktop
Team Chat
Zulip Desktop client for Mac, Windows and Linux.
Apache-2.0vs Slack★ 986ssh-chat
Team Chat
Chat over SSH.
MIT★ 5.9k
Teamgram
Team Chat
Unofficial open source mtproto server written in golang with compatible telegram client.
Apache-2.0vs Telegram★ 2.3k
Colanode
Docs & Wikis
Open-source and local-first Slack and Notion alternative that puts you in control of your
Apache-2.0vs Notion★ 5.2k
Profanity
Team Chat
Ncurses based XMPP client
OSS★ 1.5k
Session
Team Chat
Session Desktop - A Decentralized, Onion Routed, Private Messenger
GPL-3.0vs Signal★ 585