Towards 2D Traceability in a Platform for Contract Aware Visual Transformations with Tolerated Inconsistencies

Today´s model-driven engineering tools focus on the automatic transformation of software models and lack essential support for interacting with developers. This paper presents some lessons learned from building a standard compliant platform for the visual development of interactive consistency maintenance software. Based on an established requirements engineering case study, the paper illustrates the need for developer interaction and the controlled tolerance of inconsistencies. This motivates the role of traceability links in two dimensions: links between application models allow one to maintain consistency incrementally and tolerate inconsistencies in a controlled manner. In the other dimension, links between transformation models enable the refinement of declarative descriptions of consistency contracts into constructive transformations. Such transformations can be generated automatically from the contracts but tend to be optimized subtly by a transformation expert