A domain specific language for stepwise design of software architectures

Stakeholders have to face requirements in increasing number and complexity. Their translations to system functionalities are often diluted into the overall architecture so that it becomes tricky to undertake future changes. Since information systems are intended to evolve in terms of functionalities and underlying technologies, the link between requirements and design artifacts is primordial. Agile design methods and documentation techniques have emerged in the past years in order to deal with the amount of requirements and to trace the decision process and the rationale sustaining a software model. Also, it is not unusual that numerous technologies with similar purpose are confronted to each other during the design phase. In the present work, we propose an integrated framework combining system requirement definitions, a component-based modeling language and model transformations. Architecturally-significant requirements are explicitly linked to software architecture elements and iteratively refined or implemented by model transformations. Any transformation must be documented, even briefly, and the framework retains the transformations tree. This way, the iterative decision and design processes are completely documented for future reference or modification, i.e, designers can (i) see the mapping between a system requirement and its implementation in the architecture model, (ii) explore design alternatives or apply structural modifications without losing previous versions of the model, and finally (iii), depending on the level of documentation, at least understand partially the reasons why the model is how it is.