The role of Persistence layer per se is to conceptualize the repositories and the interfaces needed by mechanisms that are part of PaaSport marketplace. Regarding Execution and Coordination Layer, the functionality that is provided is complementary and refers to the provision of the interoperability between different PaaS offerings. This is achieved through the implementation of the Unified Cloud API, the PaaSport Adapters and the Interoperability/Portability Libraries (Dynamic Configuration Interface).