Mattermost

https://www.mattermost.org

See also | :gitlab :slack rocket.chat

Notes

Desktop client
https://github.com/mattermost/desktop

As an exemplar of free software
https://opensource.com/community/16/6/mattermost-shows-oss-has-be-better

Choosing over Slack and Rocket.Chat
http://www.akitaonrails.com/2016/08/13/choosing-mattermost-over-rocket-chat-and-slack



Backlinks: slack

CC0 / Public domain dedication To the extent possible under law, d3vid seaward has waived all copyright and related or neighboring rights to "Mattermost in Grasmere notebook, including code snippets" (why? how?)