Adapting requirements models to varying environments

The engineering of high-quality software requirements generallyrelies on properties and assumptions about the environment inwhich the software-to-be has to operate. Such properties and as-sumptions, referred to as environment conditions in this paper, arehighly subject to change over time or from one software variantto another. As a consequence, the requirements engineered for aspecific set of environment conditions may no longer be adequate,complete and consistent for another set.The paper addresses this problem through a tool-supported re-quirements adaptation technique. A goal-oriented requirementsmodelling framework is considered to make requirements’ refine-ments and dependencies on environment conditions explicit. Whenenvironment conditions change, an adapted goal model is computedthat is correct with respect to the new environment conditions. Thespace of possible adaptations is not fixed a priori; the requiredchanges are expected to meet one or moreenvironment-independentgoal(s) to be satisfied in any version of the system. The adapted goalmodel is generated using a new counterexample-guided learningprocedure that ensures the correctness of the updated goal model,and prefers more local adaptations and more similar goal models