1. A method, implemented using a computing system, for composing compound services, the method comprising: creating a first definition of a first service, the first service including a first interface object; creating a data exchange object that represents the first interface object of the first service; creating an association between the first interface object of the first service with the data exchange object; storing the first definition, the data exchange object, and the association; and providing, to a user, access to the first definition, the data exchange object, and the association.