Abstract: To manage forward and backward compatibility, a mechanism is provided through which evolved and synthesized property definitions may be added by a new implementation that uses data from an old implementation. The definitions are associated with code that rename, reformat or otherwise manage access to the properties for which an old schema and a new schema are different. Such mechanisms generally allow an application using a first implementation of a metadata schema to access data stored using a second implementation of a metadata schema by specifying an evolved property definition in the first implementation to refer to a corresponding property definition in the second implementation, for each property in the first implementation that is different from a corresponding property in the second implementation. Accesses are redirected using the evolved property definition to access the corresponding property definition in the second implementation.