1. A method comprising: modeling a building block component, the building block component having a behavior definition, and an information gatherer to gather information on relatedness of the building block component to components of a composite application modeled with the building block component, the relatedness based, at least in part, on the behavior of the building block component in the composite application; storing the building block component in a repository of building blocks with which to generate the composite application, including storing the relatedness information; modeling the composite application with the building block component from the repository; and modifying the behavior definition of the building block component in accordance with the relatedness information.