In the application development context, Korebi is a technology to design, develop and consume consistent, configurable and programmable APIs. These APIs absorb the impact of application logics change implementing the Api virtualization idea. Virtualization means that APIs become logic and not physically coded entities making an API architecture natively modular, extensible and customizable at runtime like Lego blocks. From the API designer/developer side this means that API don’t need to be developed and maintained: developers will focus on high added value functionalities, application logic reuse and composition. On the consumer side, API virtualization enables a brand new way to empower client code in order to request whatever is needed on whatever resource in a very simple way.