We consider specifications of analysers expressed as compositions of two functions: a semantic function, which returns a natural semantics derivation tree, and a property defined by recurrence on derivation trees. A recursive definition of a dynamic analyser can be obtained by fold/unfold program transformation combined with deforestation. A static analyser can then be derived by abstract interpretation of the dynamic analyser. We apply our framework to the derivation of a dynamic backward slicing analysis for a logic programming language.