Assessing the Architectural Quality of Evolvable Systems

Object-oriented software systems have a natural tendency to evolve. This can be due to many different reasons such as changing requirements, software maintenance, etcetera. Current trends even seem to indicate that continuously evolving systems will become the norm for most organisations. To cope with this fact, architectures and designs should be made as adaptable and reusable as possible. This is the only way to facilitate the evolution and maintenance of software systems, and to avoid them turning into legacy systems. We propose the reuse contract formalism as a methodology to make architectures and designs more reusable.