In my app, Blockusign, I am trying to prove two parties signed a copy of a document (hash).
I am a noobie to bitcoin programming and read you can accomplish this using a multi-sig and pass data into a transaction using the OP_RETURN.
I would prefer to use the bitcoin public keys that have the user’s blockstack id and attestations associated to it for proof that a “real” user signed the transaction.
Is there an easy way to do this with blockstack.js? Or do you suggest a better/different architecture?