1. Computer apparatus comprising non-transitory computer-readable medium contains instructions for managing software configuration repositories comprising: a plurality of repositories each holding a respective set of change-request objects, the plurality repositories including a primary repository and working repositories; and in the primary repository, a copy of respective proxy object for each change-request object of interest in a working repository is created in the primary repository, wherein the change-request objects of interest include any of objects that are to participate in cross-repository queries, and objects that have relationships with objects in other repositories; and each proxy object has a corresponding associated change-request object in the primary repository; wherein for a given proxy object, changes made to one of the respective change-request objects of interest in the working repository and the associated change-request object in the primary repository are mapped to the other; wherein the mapping between the respective change-request object of interest in the working repository to changes made to the associated change-request object in the primary repository comprising: incoming synchronization rules for making corresponding changes to the associated change-request object in the primary repository corresponding to the proxy object; and outgoing synchronization rules, wherein for a given proxy object, when state of the associated change-request object is updated, the outgoing synchronization rules making corresponding changes to state of the change-request object of interest, in the working repository, corresponding to the proxy object.