Abstract. We present a code generator framework for Isabelle/HOL. It formalizes the intermediate stages between the purely logical description in terms of equational theorems and a programming language. Correctness of the translation is established by giving the intermediate languages (a subset of Haskell) an equational semantics and relating it back to the logical level. To allow code generation for SML, we present and prove correct a (dictionary-based) translation eliminating type classes. The design of our framework covers different functional target languages. 1 Introduction and related work Executing formal specifications is a well-established topic and many theorem provers support this activity by generating code in a standard programming language from a logical description, typically by translating an internal functional language to an external one: