Bridging the software quality gap

Sammanfattning: There is a gap in the understanding of software quality between developers and non-technical stakeholders, the software quality gap, which leads to disagreements about the amount of time that should be used for quality improvements. The technical debt metaphor reduces this gap some by describing software quality in economic terms, enabling developers and non-technical stakeholders to communicate about the quality. However, the metaphor is vague and not very concrete in explaining the gap. The purpose of this thesis is to concretize the technical debt metaphor using Domain-Driven Design, an approach in which communicating software characteristics is central, in order to reduce the software quality gap further. Using the terminology of Domain-Driven Design, a new concept is defined: model debt, which measures and communicates the software quality of the domain model. An application is built, the ModelDebtOMeter, which extracts the domain model of a software system and visualizes it along with its corresponding model debt. The model debt of a legacy system is amortized and the results of the amortizations are presented to the non-technical stakeholders of the system using the ModelDebtOMeter, allowing the non-technical stakeholders to evaluate the model debt concept. The results show that the non-technical stakeholders think that model debt is an understandable concept which reduces, but not eliminates, the software quality gap.