Extracting software product lines: a cost estimation perspective

Companies are often forced to customize their software products. Thus, a common practice is to clone and adapt existing systems to new customer requirements. With the extractive approach, those derived variants can be migrated into a software product line. However, changing to a new development process is risky and may result in unnecessary costs. Therefore, companies apply cost estimations to predict whether another development approach is beneficial. Existing cost models for software-product-line engineering focus on development from scratch. Contrarily, the extractive approach is more common in practice but specialized models are missing. Thus, in this work we focus on product-line extraction from a set of legacy systems. We i) describe according cost factors, ii) put them in context with the development process and cost curves, and iii) identify open challenges in product-line economics. This way, our work supports cost estimations for the extractive approach and provides a basis for further research.