Open Source Alternatives To Microsoft Teams

Yet another matrix client

A glossy Matrix collaboration client for the web.

Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..

Repository for miscellaneous repository management and discussions: https://github.com/revoltchat/revolt/discussions

The communications platform that puts data protection first.

Twake is a secure open source collaboration platform to improve organizational productivity.

:wavy_dash: Overview of the open source code for Wire

Zulip server and web application. Open-source team chat that helps teams stay productive and focused.