This paper outlines a first methodology for a framework and component technology for Semantic Web applications, layered constraint frameworks. Due to the heterogeneity of the Semantic Web, different ontology languages will coexist. Applications must be able to work with several of them, and for good reuse, they should be parameterized by them. As a solution, we combine layered frameworks with architecture systems and explicit constraint specifications. Layered constraint frameworks can be partially instantiated on 6 levels, allowing for extensive reuse of components and variability of applications. Not only that applications can be instantiated for a certain product or web service family, also architectural styles, component models, and ontology languages can be reused or varied in applications. And hence, for the first time, this proposes a reuse technology for ontology-based applications on the heterogeneous Semantic Web.