Stepping Away From the Lamppost: Domain-Level Technical Debt

Background: Technical debt is a metaphor for trading software quality for business goals, reminding actors of the deferred cost associated with such trade-offs. The bulk of the literature on technical debt focuses on source code quality debt. Much less research is devoted to other forms of technical debt, such as documentation debt or architecture debt. In practice, however, we often observe technical debt pertaining to even higher-level, domain-oriented design issues. Goal: In this position paper, we aspire to bring attention to this gap in the study of technical debt and establish "domain debt" as a first class citizen in the discourse on technical debt. We aim to further this discourse by providing relevant examples and a working definition. Method: Based on many years of industrial experience, we present prototypical examples of domain debt from an industrial project, representing common design flaws of Enterprise Information Systems. We explore the origin and impact of these faults, and analyze the differences to other forms of technical debt. We use our examples to produce a working definition of the notion "domain debt". Conclusions: Domain debt is a useful notion in practice. It is suitable to steer the conversation around business trade-offs towards higher levels of system design quality. It has not been covered sufficiently in research so far, despite its relevance.