Okay, I've just deployed a bleeding edge #Fedify, which implements both RFC 9421 and double-knocking, to Hackers' Pub. If you'd like to test your implementations against a real server, please give it a try! (If you want to create an account, let me know—I can invite you.)

#fedidev #ActivityPub

@hongminhee I implemented the verification algorithm.

Would you like to run some tests? My inbox should be able to accept RFC-9421 signed requests.