1. A computer-readable medium having instructions stored thereon that, when executed by a processor, cause the processor to create a service instance, the creating comprising: receiving a service order referring to an entity as its subject, wherein the entity comprises metadata that defines a capability that is provided, and wherein the entity comprises one or more child entities; designing a configuration for the entity; wherein the configuration comprises the entity, the one or more child entities, and one or more relationships between the entity and the one or more child entities; creating, for each child entity, a design context, wherein each child entity is a subject for the design context; and designing, for each child entity, an instance of the child entity using the corresponding design context.