
Open source platform for secure collaboration across the entire software development lifecycle
Mattermost is a self-hosted, open-core collaboration platform designed for mission-critical work. It provides secure team messaging, voice calling, screen sharing, workflow automation via Playbooks, and deep integrations with DevOps tools like GitLab, Jenkins, and PagerDuty. Trusted by organizations in defense, government, healthcare, and finance, Mattermost gives teams full data sovereignty and compliance control.
Organized team communication with public/private channels, direct messages, threads, and file sharing
Automated workflow checklists for incident response, release management, and operational procedures
Built-in voice and video calling with screen sharing for real-time collaboration without third-party tools
Native integrations with GitLab, Jenkins, GitHub Actions, Prometheus, Grafana, PagerDuty, and Opsgenie
Deploy on your own infrastructure for full data custody, including air-gapped and edge environments
Built-in AI capabilities for message summarization, content generation, and workflow assistance
End-to-end encryption, MFA, SSO, granular permissions, audit logs, and compliance with industry standards
Secure ChatOps platform for coordinating software delivery, pipeline alerts, and code reviews with integrated CI/CD tool notifications
Automate incident handling with Playbooks that track diagnostics, assign tasks, and integrate with PagerDuty and Opsgenie for faster resolution
Deploy on classified or air-gapped networks with full data custody for mission-critical team communication
Meet healthcare (HIPAA) and financial compliance requirements with audit logs, data retention, and encryption controls
Best overall Slack replacement for engineering and DevOps teams. The familiar interface ensures fast adoption, while Playbooks and security features justify choosing it over the original.
Best for engineering and IT teams who want a focused, Slack-like self-hosted messaging platform with native DevOps integrations and minimal deployment overhead.
Set visibility time limits on sensitive messages and posts to minimize data exposure risks
Extensible platform with webhooks, slash commands, bots, and a plugin marketplace
Replace proprietary messaging platforms with a customizable, self-hosted solution that gives organizations full control over their data

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