Mattermost is an open-source online chat service. It is designed as an internal chat, and mostly markets itself as an alternative to Slack.
Mattermost is an open-source, self-hostable online chat service. It is designed as an internal chat for organisations and companies, and mostly markets itself as an alternative to Slack.
The code was originally proprietary, as Mattermost was used as an internal chat tool inside SpinPunch, a game developer studio, but was later open-sourced. The 1.0 was released on October 2, 2015.
The project is maintained and developed by Mattermost Inc. The company generates funds by selling support services and additional features that aren’t in the open-source edition.
There are desktop clients for Windows, MacOS, and Linux and mobile apps for iOS and Android.
In the media Mattermost is mostly regarded as an alternative to the more popular Slack. It was also integrated into GitLab as “GitLab Mattermost”, although in the meantime GitLab acquired Gitter, another popular chat tool.