Techniques for programmatically recovering broken references between a model and corresponding extensions. This preferably comprises persisting a snapshot of each extended model, along with the extensions to the model, where the extensions reference objects in the snapshot. Upon subsequently reloading the object model, the snapshot is compared to a current version of the object model. If the snapshot does not match this current version, the snapshot is preferably revised using a merge operation, such that the extensions then refer to the correct objects.