Architecting for evolvability by means of traceability and features

The frequent changes during the development and usage of large software systems often lead to a loss of architectural quality which hampers the implementation of further changes and thus the systemspsila evolution. To maintain the evolvability of such software systems, their architecture has to fulfil particular quality criteria. Available metrics and rigour approaches do not provide sufficient means to evaluate architectures regarding these criteria, and reviews require a high effort. This paper presents an approach for an evaluation of architectural models during design decisions, for early feedback and as part of architectural assessments. As the quality criteria for evolvability, model relations in terms of traceability links between feature model, design and implementation are evaluated. Indicators are introduced to assess these model relations, similar to metrics, but accompanied by problem resolution actions. The indicators are defined formally to enable a tool-based evaluation. The approach has been developed within a large software project for an IT infrastructure.