A framework is provided for generating code for the model-based development of a system. According to the framework, the model-based system is modeled using graphical modeling entities. A modular code generator routine is attached directly to at least one of the graphical modeling entities or to a meta-entity or to a collection of entities. The graphical modeling entities are traversed in order to access specified code generator routines. Each of the accessed code generator routines is executed so as to build up code portion by portion for the system.