Based on the experience in the e-commerce domain, we propose a concept for the development of higher-level transformation languages. Transformation is a key factor in this domain as the market requires a fast reaction to frequent changes in the interfaces and exchange data. Moreover, a typical e-commerce system is divided into different services which are offered and hosted by different vendors which results in a complex integration problem.

Our proposed solution is based on the operator hierarchy concept which allows to define transformation operator hierarchies containing different levels of transformation operators. The concrete realization of such a higher-level transformation language construction is demonstrated by an application of the XML operator hierarchy concept to the transformation language XSLT. XSLT serves as an example which is employed to provide the elementary transformation operators. On top of these elementary operators the layered concept allows the definition of new higher-level operators, e.g. domain-independent and domain-specific ones. The construction of the higher-level language XML2DSV is presented, for instance. This is a stand-alone domain-specific transformation language, which creates delimeter-separated values (DSV) files from XML documents, on the base of XSLT.