FlexiCore allows extending and customizing the existing behavior of solutions provided in the solution gallery by providing extensible services and domain models. 

Extending plugins is carried out by inheriting new model entities for the provided plugin ones. This is a normal Object-Oriented procedure applied when required.
Regarding services, the provided services in the service plugin may be injected into the new service plugins that may extend the business workflows and the APIs. Existing services generically support the new model entities if these extend the original model ones.
When preferred, extending the existing domain model can be implemented through FlexiCore dynamic schema support. Thus, new properties including complex objects can be added to an existing entity.