A Case Study on the Evolution of a Component-based Product Line

Product line engineering is an approach that works well for managing the anticipated variability of software systems as demonstrated in numerous studies. However, little empirical research and few approaches exist for dealing with the unanticipated evolution of product lines. As a result, the understanding of product line evolution is still weak and the maturity of approaches and tools supporting evolution is often insufficient. In this paper we present results of a case study on impact analyses and desired tool support in product line evolution. Our findings are based on observing 30 person months of development. We analyzed changes made to a product line in typical evolution scenarios by involving the key developers. We used empirical data on observed development activities and impact analyses to derive a trace information model showing frequently desired trace links. We discuss lessons learned and implications for tool developers.