Computer language paradigms offer linguistic abstractions and proof theories for expressing program implementations. Similarly, system architectures offer the hardware abstractions and quantitative theories applicable to the execution of compiled programs. Although the two entities are usually treated independently, object-oriented technology can be used to obtain a unifying framework. Specifically, inheritance can be used to model both programming languages as extensions to the assembly language executed by the target architecture, and system architectures as the root class of those paradigms. We describe how these principles can be used to model, structure and implement real multiparadigm systems in a portable and extendable way. 1 Motivation Computer language paradigms offer linguistic abstractions and proof theories for expressing program implementations. Similarly, system architectures offer the hardware ions and quantitative theories applicable to the execution of compiled progra...