Mattermost
Open-source alternative to Microsoft Teams, Slack, Guilded.
Mattermost provides a flexible, open-source platform for secure team collaboration, designed for organizations with strict security and privacy requirements.
Open Source Alternative to:

Mattermost provides a flexible, open-source platform for secure team collaboration, designed for organizations with strict security and privacy requirements.
Some key features of Mattermost:
- Open-source alternative to Microsoft Teams, Slack, Guilded
- Collaboration & Communication and Data Security & Privacy coverage
- GitHub stars, forks, license, last commit, and activity score synced from directory sources
- Codex course and interactive classroom previews attached to the repository detail page
Learning previews
Learn this project
Codex HTML Course
Mattermost Codex HTML Course
Mattermost Codex HTML Course is being prepared for this directory project.
Interactive Classroom
Mattermost Interactive Classroom
Mattermost Interactive Classroom is being prepared for this directory project.
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