diff --git a/pkgs/applications/video/key-mon/default.nix b/pkgs/applications/video/key-mon/default.nix
index 5b3c94ab2719..5d1a0e4a95b6 100644
--- a/pkgs/applications/video/key-mon/default.nix
+++ b/pkgs/applications/video/key-mon/default.nix
@@ -15,8 +15,8 @@ buildPythonPackage rec {
 
   doCheck = false;
 
-  makeWrapperArgs = ''
-    --set GDK_PIXBUF_MODULE_FILE ${librsvg}/lib/gdk-pixbuf-2.0/2.10.0/loaders.cache
+  preFixup = ''
+      export makeWrapperArgs="--set GDK_PIXBUF_MODULE_FILE $GDK_PIXBUF_MODULE_FILE"
   '';
 
   meta = with stdenv.lib; {