diff --git a/nix/crlcore.nix b/nix/crlcore.nix
index 4adad541..b422c181 100644
--- a/nix/crlcore.nix
+++ b/nix/crlcore.nix
@@ -2,10 +2,10 @@
 let pkg =
   { lib, libxml2, qt4, bison, flex, doxygen, coriolis-vlsisapd
   , coriolis-lefdef, coriolis-hurricane, python2Packages }:
-  {
+  rec {
     name = "crlcore";
     src = ../crlcore;
-    buildInputs = [ libxml2 qt4 coriolis-lefdef coriolis-vlsisapd coriolis-hurricane python2Packages.pyqt4 ];
+    propagatedBuildInputs = [ libxml2 qt4 coriolis-lefdef coriolis-vlsisapd coriolis-hurricane python2Packages.pyqt4 ];
     nativeBuildInputs = [ bison flex doxygen python2Packages.pyqt4 ];
     postInstall = ''
       ln -s crlcore/helpers $out/${python2Packages.python.sitePackages}/helpers
diff --git a/nix/generic.nix b/nix/generic.nix
index f16a0517..9f64a2fa 100644
--- a/nix/generic.nix
+++ b/nix/generic.nix
@@ -12,6 +12,7 @@ let
       , meta ? {}
       , pythonImportsCheck
       , continuation ? (x: x)
+      , postInstall ? ""
       , ...
       }@args':
       let
@@ -26,11 +27,11 @@ let
             python2Packages.pythonImportsCheckHook
           ] ++ nativeBuildInputs;
 
-          preInstall = ''
+          postInstall = postInstall + ''
               export PYTHONPATH="$out/${python2Packages.python.sitePackages}:$PYTHONPATH"
           '';
 
-          meta = meta // meta';
+          meta = meta' // meta;
 
           inherit version pythonImportsCheck;
         } // args);
diff --git a/nix/oroshi.nix b/nix/oroshi.nix
index b3e3c39b..685ca9f8 100644
--- a/nix/oroshi.nix
+++ b/nix/oroshi.nix
@@ -7,7 +7,7 @@ let pkg =
     name = "oroshi";
     src = ../oroshi;
 
-    buildInputs = [
+    propagatedBuildInputs = [
       coriolis-vlsisapd qt4 python2Packages.pyqt4
       coriolis-crlcore coriolis-hurricane qt4
       python2Packages.numpy
diff --git a/nix/unicorn.nix b/nix/unicorn.nix
index 4f5deb2e..6fa46ae0 100644
--- a/nix/unicorn.nix
+++ b/nix/unicorn.nix
@@ -6,19 +6,23 @@ let pkg =
   , coriolis-flute, coriolis-anabatic, coriolis-coloquinte
   , coriolis-lefdef, coriolis-knik, coriolis-kite
   , coriolis-katabatic, coriolis-etesian, coriolis-equinox
-  , coriolis-solstice, libxml2, doxygen }:
+  , coriolis-solstice, libxml2, doxygen, python2Packages }:
   {
     name = "unicorn";
     src = ../unicorn;
 
-    buildInputs = [
+    propagatedBuildInputs = [
       coriolis-vlsisapd coriolis-hurricane coriolis-crlcore
       coriolis-katana qt4 coriolis-flute coriolis-anabatic
       coriolis-lefdef libxml2 coriolis-knik coriolis-kite
       coriolis-katabatic coriolis-etesian coriolis-equinox
       coriolis-solstice
     ];
-    nativeBuildInputs = [ doxygen ];
+    nativeBuildInputs = [ doxygen python2Packages.wrapPython ];
     pythonImportsCheck = [ "Unicorn" ];
+
+    postFixup = ''
+      wrapPythonPrograms
+    '';
   };
 in generic pkg