Open source, self-hosted Slack-alternative.
Workplace messaging for web, PCs & phones with native apps. MIT-licensed. Hundreds of contributors. 10 languages. Secure, extendable, and scalable from teams to enterprise.
Ranked in these QuestionsQuestion Ranking
Pro Can be self-hosted
You don't need to rely on someone else's servers, you can host Mattermost on your own server.
Pro One-line Docker install
With Docker set up, you can install Mattermost with the following command:
docker run --name mattermost-dev -d --publish 8065:80 mattermost/platform
For other cases, installation instructions can be found here.
Pro Similar to Slack
Almost all features of Slack are available in Mattermost.
Pro Free - OpenSource
You can download and use it as free for self-hosted server.
Pro Mark-Down support
Yes, it supports markdown.
Pro Browser notifications
Pro Desktop app for MacOS, Linux and Windows
Pro Mobile apps for android and iOS
Pro You can change theme
This doesn't work for every type of company. Mainly great for those concerned with privacy, security, compliance and control of your data/information.