Hi Bas. > I'm hitting on an issue when deriving Generic for an associated data type: [...] Your example compiles for me with HEAD (but fails with 7.4.1 and 7.4.2, yes). I've not tested if it also "works". Cheers, Andres -- Andres Löh, Haskell Consultant Well-Typed LLP, http://www.well-typed.com