# Mattermost

> Mattermost is an open-source, self-hostable collaboration platform built for organizations that cannot put their conversations in someone else's cloud. Started as a game studio's internal chat tool and open-sourced in 2015, it grew into the leading self-hosted alternative to Slack and Microsoft Teams, combining channel messaging, voice and screen sharing, incident-response Playbooks, and integrated AI agents. Its customers skew toward defense, government, financial services, and technology organizations - from the U.S. Air Force to Uber - that need data sovereignty, air-gapped deployment, and government-grade security.

- **Founded:** 2015
- **Headquarters:** Palo Alto, California, United States
- **Founders:** Ian Tien (Co-founder & CEO), Corey Hulen (Co-founder & CTO)
- **Team size:** ~160-165 employees
- **Products:** Channels, Playbooks, Calls, Boards, Agents (AI)
- **Notable:** Grew from a failed game studio's internal tool into the leading open-source Slack alternative, powering 800,000+ workspaces., Attracted 4,000+ community contributors to its open-source codebase., Raised $70M+ total, including a $50M Series B led by Y Combinator Continuity in 2019.

## Products & services

- **Channels** — Core team messaging with channels, direct messages, threaded chat, file sharing, search, and cross-platform desktop and mobile clients.
- **Playbooks** — Structured, checklist-driven workflows for incident response and standard operating procedures, with assigned tasks, due dates, and automated status updates.
- **Calls** — Secure, self-hosted voice calls and screen sharing directly inside channels and direct messages, with membership-based access controls.
- **Boards** — Kanban-style project and task management integrated into the collaboration workspace.
- **Agents (AI)** — Integrated AI agents that can use sovereign or third-party LLMs, act inside the channel where work happens, and ground answers in the team archive.
- **Intelligent Mission Environment (IME)** — A sovereign, AI-integrated platform bundle for defense, government, and critical infrastructure - combining Channels, Playbooks, Calls, Agents, and Enterprise Advanced security.

## Achievements

- Grew from a failed game studio's internal tool into the leading open-source Slack alternative, powering 800,000+ workspaces.
- Attracted 4,000+ community contributors to its open-source codebase.
- Raised $70M+ total, including a $50M Series B led by Y Combinator Continuity in 2019.
- Adopted by mission-critical organizations including the U.S. Air Force, NASA, Nasdaq, and the European Parliament.
- Reported improving the U.S. Air Force's information availability by 4x.
- Launched the Intelligent Mission Environment (2025), extending into sovereign AI for classified operations.

## Latest updates

- **2026** — Introduced Mattermost Agents V2, letting teams build, own, and deploy AI agents that act directly in the channels where work happens.
- **2025-06** — Announced the Intelligent Mission Environment (IME), a sovereign, AI-integrated platform for DevSecOps, incident response, and mission-critical operations.
- **2025-06** — Joined the inaugural cohort of the Oracle Defense Ecosystem for sovereign AI collaboration.
- **2025** — Launched Mattermost Enterprise Advanced with agentic AI, workflow automation, and advanced security controls, and introduced 'Mattermost Entry' as the new free edition for small teams.
- **2025-01** — Announced intent to deliver AI-powered collaboration for Azure Secret and Top Secret classified cloud environments.

## Links

- Website: https://mattermost.com
- LinkedIn: https://www.linkedin.com/company/mattermost
- Twitter/X: https://twitter.com/mattermost
- GitHub: https://github.com/mattermost/mattermost
- YouTube: https://www.youtube.com/channel/UCNR05H72hi692y01bWaFXNA
- Facebook: https://facebook.com/Mattermost-2300985916642531/

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Profile page: https://yespress.io/mattermost
Published by YesPress — https://yespress.io
Last updated: 2026-07-11