Introduction

The implementation of a product line consists of a set of reusable components, called core assets, which are composed and configured in different ways to build different concrete products. The goal of a product line to support multiple products introduces additional complexity both to its assets and to the development process. The assets are more complicated because they must deal with variations of the concrete products. The development process is more complicated because it must deal not only with evolution of the common assets, but also with independent evolution of products and instantiation of new products.

In order to reduce the complexity of the implementation of a product line and to facilitate independent evolution, it is desirable to modularise the core features of a product line and the specific features of individual products. Considering features as units of variation in a product line, our goal is to support feature-oriented decomposition of software, in which each feature is implemented in a separate module.