How “Specification by Example” and Test-Driven Development Help to Avoid Technial Debt

This paper is an industrial experience report of applying the "Specification by Example" methodology and test-driven development to the development of a core component of a healthcare product. The methods are mapped to the four quadrants of technical debt introduced by Martin Fowler in order to show how they can help to avoid the accumulation of technical debt. The resulting data show that a very low defect density can be achieved with these practices, which helps to avoid technical debt introduced for example by quick fixes during a late project phase. Performance indicators measured during development and system test are presented. These results are informally compared to approaches based on formal methods further indicating the advantage of the presented approach.