Mattermost
Open-source team messaging for mission-critical work — self-hosted, air-gappable, with playbooks, AI agents, and integrations for DevOps and defence teams.
European project management alternative based in Germany.
Mattermost is an open-source team messaging and collaboration platform built for organisations that require complete deployment control — on-premises, private cloud, or air-gapped environments where messages never touch a third-party server. It delivers persistent channels, threaded conversations, and integrated AI workflows with the security controls demanded by defence, government, and critical infrastructure teams.
Playbooks automate repeatable incident response and operational workflows directly inside the messaging interface. Integrations with GitLab, Jira, PagerDuty, and Microsoft Teams bridge DevOps and operations toolchains, while a REST API and webhook system connect any custom service. Mobile apps and a desktop client support field and remote teams.
Key benefits:
- Self-hosted deployment — on-premises, private cloud, or air-gapped with no external dependencies
- Persistent channels and threads for organised, searchable team communication
- Playbooks for automated incident response and repeatable operational runbooks
- AI agents for workflow automation and intelligent assistance inside channels
- GitLab, Jira, and PagerDuty integrations for DevOps and incident workflows
- SOC 2 and GDPR compliant with FedRAMP authorization for public sector deployments
- Open-source (MIT licensed) with an active community and commercial enterprise edition
- Custom data retention and E2E encryption options for regulated environments
Open-source and deployable in any jurisdiction, Mattermost can run on EU-owned infrastructure with full GDPR compliance — no message content, metadata, or user data leaves your servers. The platform holds SOC 2 compliance and FedRAMP authorization for regulated public and private sector use.
Deployed by the U.S. Air Force, NASA, Samsung, and RTE (France) for secure, sovereign team communications in mission-critical environments.
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