This article shows the reengineering of the persistence tier of the open source software DSpace, to introduce a lower coupling in its software layers. The prototype was made using design patterns and standards from J2EE world: Domain Store, Session Façade, Application Service, JPA were also introduced for a technological upgrade of the platform. The research and development activity aimed at this goal was accomplished in a stage offered by CILEA to achieve a degree in Computer Science Engineering, an opportunity that CILEA offers on several innovative ICT themes, with the support of its experts.