Using the doughnut model to support sustainable quality requirements in iStar

Paper in proceeding, 2020

Sustainability has become a critical topic, not only from an environmental perspective, but in the creation of software systems which are themselves sustainable. The sustainability literature has made use of the doughnut model from economics to understand the delicate balance needed for sustainable development. This model emphasizes the notion of having just the right amount of a resource (e.g., food, water) and not too much, else negative consequences (water depletion, starvation) may be felt by others in the ecosystem. Although iStar has covered well the notion of trade-offs between qualities (e.g. security vs. usability, performance vs. maintainability), the implicit aim of the work is always to maximize qualities. In this work we aim for “just enough” quality by applying the doughnut economic model to quality requirements in iStar. Overall, we propose a visually appealing model which emphasizes a sustainable balance between qualities.