Application Architecture Discovery - Towards Domain-driven, Easily-Extensible Code Structure

The architecture of a software system and its code structure have a strong impact on its maintainability -- the ability to fix problems, and make changes to the system efficiently. To ensure maintainability, software systems are usually organized as subsystems or modules, each with atomically defined responsibilities. However, as the system evolves, the structure of the system undergoes continuous modifications, drifting away from its original design, leading to functionally non-atomic modules and intertwined dependencies between the modules. In this paper, we propose an approach to improve the code structure and architecture by leveraging the domain knowledge of the system. Our approach exploits the knowledge about the functional architecture of the system to restructure the source code and align physically with the functional elements and the re-usable library layers. The approach is validated by applying to a case study which is an existing financial system. The preliminary analysis for the case-study reveals that the approach creates meaningful structure from the legacy code, which enables the developers to quickly identify the code that implements a given functionality.