Mattermost
Open source team communication you host yourself
Open sourceOpen sourceMattermost is an open source team communication service. It offers channels and messaging with apps for all the major platforms, and was designed with developer teams in mind, although it works just as well for any other kind of team. The whole thing can be self-hosted.
Mattermost is self-hosted open source software and is not necessarily European: the location of your data depends entirely on where you install it. Run it on a server in the EU and it becomes a European alternative to the American chat platforms. It suits engineering teams and organisations that need full control over their conversations.
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