diff --git a/casadi-bindings.cabal b/casadi-bindings.cabal
--- a/casadi-bindings.cabal
+++ b/casadi-bindings.cabal
@@ -1,5 +1,5 @@
 name:                casadi-bindings
-version:             2.4.1.8
+version:             2.4.1.9
 synopsis:            mid-level bindings to CasADi
 category:            Numerical, Math
 description:
diff --git a/cbits/handwritten.cpp b/cbits/handwritten.cpp
--- a/cbits/handwritten.cpp
+++ b/cbits/handwritten.cpp
@@ -1,31 +1,11 @@
-//#include <casadi/casadi.hpp>
-//#include <cmath>
-//#include <stdexcept>
-//#include <iostream>
-//
-//extern "C"
-//casadi::GenericType *
-//custom_generic_dictionary(std::string ** err_msg,
-//                          std::vector< std::string* >& keys,
-//                          std::vector< casadi::GenericType* >& vals);
-//
-//casadi::GenericType *
-//custom_generic_dictionary(std::string ** err_msg,
-//                          std::vector< std::string* >& keys,
-//                          std::vector< casadi::GenericType* >& vals) {
-//    try {
-//        const int nk = keys.size();
-//        const int nv = vals.size();
-//        if (nk != nv) throw "dictionary key/value length mismatch";
-//        
-//        casadi::Dictionary dict;
-//        for (int k = 0; k < nk; k++)
-//            dict.insert(std::pair<std::string,casadi::GenericType>(*(keys[k]), *(vals[k])));
-//
-//        return new casadi::GenericType(dict);
-//
-//    } catch (std::exception& ex) {
-//         *err_msg = new std::string(ex.what());
-//         return 0;
-//    }
-//}
+#include "math.h"
+
+extern "C" double c_fmod(double x, double y);
+double c_fmod(double x, double y) {
+  return fmod(x, y);
+}
+
+extern "C" float c_fmodf(float x, float y);
+float c_fmodf(float x, float y) {
+  return fmodf(x, y);
+}
diff --git a/src/Casadi/Overloading.hs b/src/Casadi/Overloading.hs
--- a/src/Casadi/Overloading.hs
+++ b/src/Casadi/Overloading.hs
@@ -9,15 +9,17 @@
        , ifLeqThen, ifGeqThen, ifEqThen, ifLtThen, ifGtThen
        ) where
 
-import Data.Fixed ( mod' )
+import Foreign.C.Types ( CDouble(..), CFloat(..) )
 import SpatialMath ( ArcTan2(..) )
 
 -- | doesn't require Real, used for overloading symbolics
 class Fmod a where
   fmod :: a -> a -> a
 
-instance Fmod Double where fmod = mod'
-instance Fmod Float where fmod = mod'
+foreign import ccall unsafe "c_fmod" c_fmod :: CDouble -> CDouble -> CDouble
+foreign import ccall unsafe "c_fmodf" c_fmodf :: CFloat -> CFloat -> CFloat
+instance Fmod Double where fmod x y = realToFrac $ c_fmod (realToFrac x) (realToFrac y)
+instance Fmod Float where fmod x y = realToFrac $ c_fmodf (realToFrac x) (realToFrac y)
 
 -- | error function
 class Erf a where