By Alexander Palm, paluno (The Ruhr Institute for Software Technology), University of Duisburg-Essen, Essen, Germany | Felix Feit, paluno (The Ruhr Institute for Software Technology), University of Duisburg-Essen, Essen, Germany | Andreas Metzger, paluno (The Ruhr Institute for Software Technology), University of Duisburg-Essen, Essen, Germany