Don't Worry About it: Managing Variability On-The-Fly

Software-product-line engineering (SPLE) has become a widely adopted concept to implement reusable source code. However, instead of using SPLE from the beginning (the proactive approach), a software product line ( SPL) is often only introduced after a set of similar systems is already developed (the extractive approach). This can lead to additional costs, new bugs introduced by refactoring, and an overall inconsistent SPL. In particular, inconsistencies between the variability implemented in the source code and the one represented in a variability model can become a major problem. To address this issue, we propose the concept of variability management derivation: We aim to (semi-)automatically model features and their dependencies while developers implement variable source code to facilitate the initial development, reusability, and later maintainability of SPLs, utilizing the reactive approach. In this paper, we demonstrate our concept by means of preprocessors. However, we claim that it can be adapted for other SPLE implementation techniques to facilitate SPL development.