i only say this because i don't think it's well documented, members only seem to get 1 invite per week iirc, so this is likely a big ask. good luck getting on there. OP!
It is releasing its own federated protocol, seems like it does a lot more than activitypub. Your account identity is valid on any instance, for example
BlueSky is a private social media app and a direct competitor to Twitter. It was created by Jack Dorsey, formerly of Twitter, who encouraged and endorsed Elon Musk's purchase of Twitter. (Maybe this was a brilliant double cross.) I think the one difference between Twitter and BlueSky is users of BS (ha, I wonder if they thought of this abbreviation when they named their app) can edit the algorithm on BlueSky.