The purpose of the Compositional Interchange Format for hybrid systems (CIF) is to establish inter-operability of a wide range of tools by means of model transformations - using the CIF as intermediate, the implementation of many bi-lateral translators between specific formalisms can be avoided. This paper presents the architecture of the CIF transformation framework. Languages in the CIF transformation framework are defined by means of conceptual models, and transformations are specified by means of transformation languages. To avoid large monolithic transformations, transformations are divided into many small single- or crossformalism transformations, each with their own concern. In this way, transformations are obtained that are easier to understand and can be re-used individually. A domain-specific language ToolDef has been developed to specify complex, automated tool chains that are based on these small individual transformations. The ToolDef architecture is illustrated using a translation between the CIF and UPPAAL, and an example for the application of the transformation framework is given based on a transformation between the CIF and gPROMS.