We analyze an approach to software development where object-oriented and compositional software specifications are written in separate languages and are only loosely connected. It supports compositional design of software in a domain-specific language and automatic model-driven construction of code from classes written in Java. We justify our approach by giving examples of development of large simulation programs and services on large models. We present also an example of using our method in general purpose software development - this is bootstrapping the essential part of a software tool CoCoViLa, i.e. synthesizing CoCoViLa in CoCoViLa itself.

A way of combining object-oriented and structural paradigms of software composition is demonstrated in a tool for generative programming. Metaclasses are introduced that are components with specifications called metainterfaces. Automatic code generation is used that is based on structural synthesis of programs. This guarantees that problems of handling data dependencies, order of application of components, usage of higher-order control structures etc are handled automatically. Specifications can be written either in a specification language or given visually on an architectural level. The tool is Java-based and portable.