Software systems are embedded into daily life and as such have significant effects on the behavior and decision making of both their users and the people affected by using these systems. Such effects can be positive or negative. Considering them in requirements engineering (RE) is an important step towards sustainable development, as RE strongly influences the development and the evolution of a software system.
So far, RE researchers have focused on requirements about minimizing negative environmental effects. However, effects that are enabled by using a software system can also be positive. For example, a software system could motivate its users to take environment-friendly decisions. Corresponding requirements about such positive enabling effects have been far less addressed.
In this paper, we present an exploratory case study where we elicited requirements about positive enabling effects with respect to environmental sustainability. The project we studied is about extending an existing decision support system for meal planning in canteens by game-based elements. The extended system shall motivate meal planners who work in canteens to make environment-friendly choices.
Our contribution is an exemplar of concrete sustainability requirements as well as insight into the nature of sustainability requirements about positive effects that are enabled by the use of a software system.