Mattermost Beta
Secure team chat on your server.
Description
Mattermost is a secure messaging app for your team, hosted on your own server. Chat privately or in groups, share files, and connect tools via webhooks. It works with Slack integrations. Requires Mattermost Server v9.11.0+. Host your server, check terms, or contribute on their official sites. Note: Some source code isn't fully free.