the implementation

the spec is hard to read, i could try and write it based on the spec, i may yet, it's just not a high priority for me right now

i don't quit have my head wrapped around how it works but HMACs are annoying anyway, signatures do the same thing, and if the thing inside is signed and only the receiver can unpack that then there is security, and if the client can maintain the state of that, it could turn into a chain if you sent one or more future pubkeys to reply with, since the sender can identify a reply by that

but i think it's lower priority than getting everyone to fully support NIP-42 so the relays don't hand out these messages to anyone who hasn't proved they are the valid parties to the messages