A system and method for generating run-time images of a software program, such as an operating system, builds a run-time image from a plurality of selected software program components, each of which is a discrete packet of functionality. Each component not only specifies its properties and resources but also provides script for its own build behavior. To build the run-time image, a configuration is constructed to include instances of selected components, and the scripts of the instances are invoked such that each component instance builds itself into the run-time image. A prototyping scheme is provided for a component to inherit its properties, resources, and script from other components.