@rosano Solid gives you an inbox. The documentation at solidproject.org (I think) used to have a nice walkthrough that demonstrates how you can POST to someone else's inbox (using XMPP-inspired examples involving Romeo and Juliet IIRC). You can also listen for updates to Solid resources using WebSockets—or at least that used to be the case. In theory, building a group bugtracker is possible with Solid, but the UIs for the demos have always been awful (basically unusable). cc @m5x5