No, not relay based, it’s nip-05 based. But you have a Primal nip-05 and that’s super generic so you don’t really fall under a community. For example, I have a bitcoindistrict.org nip-05 (our nip is not working at the moment) but it shows me all the users who have that domain, as a community, only their posts show up. It’s pretty neat to catch up on your small circle of friends.