Flexible support for managing evolving software product lines

In software product line engineering, core assets are shared among multiple products. Core assets and products generally evolve independently. Developers need to capture evolution in both contexts and to propagate changes in both directions between the core assets and the products. Current version control systems have no support for these tasks and this may be one reason for the slow adoption of the product line approach. We address these issues with a prototype version control system that is designed to support product line engineering, but without imposing a strong process model. The prototype is being tested on the DITA documentation standard. It supports evolution of core assets and of products, as well as propagation of changes from core assets to products and vice versa.