Tools are crucial for the promotion of graph and model transformation in industry. Currently, a variety of tool environments exist for different graph and model transformation approaches. However, for potential users, working in application domains where transformation techniques may be useful, it is difficult to select the right tool for their purpose. Moreover, even for most of the tool experts it is true that they know about one or two tools but little about others. Finally, the tool developers themselves can also be inspired by a more detailed understanding of related approaches.
The aim of the Transformation Tool Contest (TTC, formerly GraBaTs) is to compare the expressiveness, the usability and the performance of graph and model transformation tools along a number of selected case studies. That is, we want to learn about the pros and cons of each tool considering different applications. A deeper understanding of the relative merits of different tool features will help to further improve graph and model transformation tools and to indicate open problems.