A method includes receiving a consensus agreement rule (“CAR”) comprising identities of a first party and second party; receiving a first SignedData message comprising first content and a first digital signature; creating a second SignedData message comprising a second digital signature of the second party on a hash of the second content and an acceptance indication; verifying, based on the acceptance indication and based on the identities on the CAR matching the identities on the signatures, that the second party accepted the terms of the agreement; and transmitting the second SignedData message to a trusted party for posting to a distributed ledger, wherein the terms of the agreement are kept private while the second SignedData message is posted to the distributed ledger, and wherein the terms of the agreement are formatted as a smart contract whose execution causes a transfer of value in response to a fulfillment of a condition.