The initial situation was an existing advisory services web application combining different aspects in a single backend, supplemented with additional business logic implemented as stored procedures in a relational database. We supported the customer in rebuilding the existing functionality as modularised web frontends and backend web services, using the database for persistence only.
A major part of the project was to rebuild the component to execute suitability and monitoring checks for security portfolios. We addressed the topics of performance, complexity and quality together with the client. The goal was to provide a solution for implementing new checks with less effort and higher reliability to roll out the application to additional countries.
Thanks to the client’s trust, close cooperation and interdisciplinary teams, our experts were able to contribute their full experience in application modernisation, agile methods and the highly complex challenges presented by the project. These were the success factors for achieving the project goal, which was to replace the database-centred solution consisting of stored procedures and database views with a backend-based solution providing a web service as the entry point.
The following sections describe how we migrated the operational production system from the initial to the target scenario. You will also see how we used behaviour-driven development, domain-driven design and agile testing to proceed iteratively with fall-back strategies, and what the resulting improvements were in terms of performance, quality and maintainability.