Digitally signing JSON messages

Systems and techniques are described for digitally signing JavaScript Object Notation (JSON) messages. One of the techniques includes receiving a JavaScript Object Notation (JSON) message; and digitally signing the JSON message, wherein digitally signing the JSON message comprises: generating a digital signature information JSON object; inserting the digital signature information JSON object into the JSON message; generating a canonical representation of the JSON message with the inserted digital signature information JSON object; generating a digital signature of the canonical representation of the JSON message; and inserting the digital signature into the digital signature information JSON object.