Introduction

Variability management is a key challenge in software product line engineering (SPLE), as reflected in challenge 2 (identifying commonalities) introduced in Chapter 1. A software product line (SPL) is all about identifying, modelling, realising and managing the variability between different products in the SPL.

Variability management has two major parts: modelling the variability an SPL should encompass; and designing how this variability is to be realised in individual products. For the former part, different kinds of variability models can be employed: a typical approach is to use feature models (Kang et al., 1990) (or cardinality-based feature models, see Czarnecki et al. (2005b), in some cases), but domain-specific languages (DSLs) have also been used with some success. The latter part – modelling how variability is realised – is less well understood. Some approaches have been defined and will be discussed in Section 4.2, including their limitations. In this chapter, we therefore focus on DSLs for variability management and present a novel approach developed in the AMPLE project that aims at overcoming these limitations.