1. A method comprising: at one or more computing device comprising one or more processors and memory storing one or more programs executed by the one or more processors to perform the method, performing operations comprising: receiving a first update to a data object; updating the data object in a first database based on the first update; receiving a second update to the data object; responsive to receiving the second update, detecting a concurrency conflict between a first value for a first property of the data object in the first database and a second value for the first property in the second update; updating the data object in the first database based on the second update only after the concurrency conflict is deconflicted; wherein the second update comprises one or more values for one or more other properties of the data object; and wherein the operation of updating the data object in the first database based on the second update only after the concurrency conflict is deconflicted comprises the operation of updating the data object in the first database based on the one or more values for the one or more other properties of the data object only after the concurrency conflict is deconflicted.