@baris I'm messing around with NodeBB on localhost, but I don't think I really understand what you suggested. After I create a group, can you let me know in which category should I create the subcategory for this group? I guess it will be even less clear for non-admin users to do this if I allow everyone to create groups? Also, I still don't see how group members will know which groups they may have access to. I think the UX can be better if group members can create categories and topics right in the group page like buddypress? I believe the users will appreciate that more.