codingquark is a user on mathstodon.xyz. You can follow them or interact with them if you have an account anywhere in the fediverse.
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For some time now, I and a friend have been working on a messaging application called Potato. It's essentially an open-source, self-hosted version of Slack.
The server part is quite stable and fast, and has been in production for some time.
The web interface is currently quite bad, and I'm really terrible at web design. If anyone wants to help out bringing this project to a point where it can be used by non-technical people, web-design help would be gladly accepted.
@loke
I haven't checked any details, but first thing that came to mind was matrix.org and xmpp.
