Mantaining design knowledge in system development

The design knowledge apparatus resulting from large systems prototyping cannot remain a single developer's kept-in-mind experience. Since this information is often hidden into the language used for the prototypical components, we present an approach based on a sharp distinction between the object-oriented language, in which components are described, and the design schema, in which components are assembled into a system. The information related to the design, structure and experienced behavior of the application under development grows along the prototyping process within the representation schema, and remains available at the implementation level.