Abstract. The today's applications usually form a system of sub-applications, each being responsible for a particular functionality. Hence, the design and maintenance of such a complex system is not a simple task. In addition, the user requirements can change and the affected parts need to be identified and evolved. Similarly, new components or even whole system may need to be integrated. In this paper we describe a framework that enables one to face the described issues. For this purpose we exploit verified technologies, such as conceptual modeling, data semantics, matching algorithms etc. Using a set of examples we show that our approach enables one to design, maintain, and evolve a system of applications efficiently and precisely. We depict the features on an XML system represented by a set of web services that exchange XML data. However, the concepts are general and can easily be extended for any kind of data format.