Studying the evolution of software systems using evolutionary code extractors

Software systems are continuously changing and adapting to meet the needs of their users. Empirical studies are needed to better understand the evolutionary process followed by software systems. These studies need tools that can analyze and report various details about the software system´s history. We propose evolutionary code extractors as a type of tool to assist in empirical source code evolution research. We present the design dimensions for such an extractor and discuss several of the challenges associated with automatically recovering the evolution of source code.