A computer method and system provides on-demand transformation between objects of a source programming model and corresponding objects in a target programming model. For different source objects in the source programming model, the invention creates respective target objects. For every created target object, the invention system and method create a respective proxy object. Where a source object has multiple features, the proxy object triggers transformation of a feature only upon access of that feature and the corresponding target object. The present invention operates transparently to a client. Thus, clients do not have to call transform on the feature (children and references) of the source object before accessing any feature of the target object.