@[email protected] yes, categories can be followed, and they actike Guppe groups. Right now you can't compose directly to a category but that's something I'll be working on soon! Category actors in NodeBB can follow other actors too, just like regular users. Any content posted by followed users will be boosted by the category. So if you have two categories that follow one another, which there are a couple between NodeBB and SocialHub (running Discourse), they're synced up!