diff --git a/itk-snap.nix b/itk-snap.nix
index 50d848f..ff0da61 100644
--- a/itk-snap.nix
+++ b/itk-snap.nix
@@ -23,7 +23,11 @@ stdenv.mkDerivation {
     qt6.wrapQtAppsHook
   ];
   buildInputs = [
-    itk
+    (itk.overrideAttrs (
+      finalAttrs: previousAttrs: {
+        cmakeFlags = previousAttrs.cmakeFlags ++ [ "-DModule_MorphologicalContourInterpolation=ON" ];
+      }
+    ))
     vtk
     qt6.qtbase
   ];