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Mattermost

Mattermost is a flexible, open source messaging platform that enables secure team collaboration. 

Secure, self-hosted, and scalable messaging that bring together conversations, files and systems into a single view so teams can work better together. Open source, private cloud Slack-alternative. Linux binary on MySQL/Postgres under MIT. YC-backed.

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Changes made by: julioell at 2019-10-19, changes message: Add "Mattermost"