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.

In the automotive field, software development methods and tools are used to cope with the high complexity of automotive software development. However, problems occur with the tracing of information, the assessment and monitoring of the development status, late and thus expensive changes, etc, which lead to increasing development costs and time as well as quality deficits. Our experience with recent projects have shown that the key to solving these problems lies in providing proper answers to the following questions: (1) How can development methods be assembled? (2) How can the use of a variety of development methods be supported by an appropriate tool? To answer these questions, we introduce a tool integration approach that is strongly based on the integration of development methods. The contribution of this paper is (a) a method integration approach that considers finegrained method objects and their specific structure in addition to the usually considered artifacts, (b) an approach to tool integration that overcomes the deficits of heterogeneous tool environments and utilizes the results of the methodical understanding.