Mattermost collaboration platform

Mattermost is an open-source, self-hostable collaboration platform designed for high-security environments, specifically catering to technical and operational teams. Originally developed as an internal tool by the game studio SpinPunch, it was open-sourced in 2015 and has since grown into a leading alternative to proprietary platforms like Slack and Microsoft Teams. The software is written primarily in Go and React and is distributed under an open core model.

While the company is headquartered in Palo Alto, California, Mattermost operates as a remote-first organization with a global network of over 4,000 contributors. As a digital software product, its 'manufacturing' or development occurs primarily in the United States, though its open-source nature means code is contributed from around the world. The company is venture-backed by prominent investors like Redpoint, Battery Ventures, and Y Combinator, and it serves high-stakes clients including the U.S. Department of Defense and various Fortune 500 companies.