apple-sdk: add MetalKit

pkgs/os-specific/darwin/apple-sdk/default.nix

@@ -211,6 +211,13 @@ in rec {
           --replace "QuartzCore/../Frameworks/CoreImage.framework/Headers" "CoreImage"
       '';
     });
+
+    MetalKit = stdenv.lib.overrideDerivation super.MetalKit (drv: {
+      installPhase = drv.installPhase + ''
+        mkdir -p $out/include/simd
+        cp ${lib.getDev sdk}/include/simd/*.h $out/include/simd/
+      '';
+    });
   };
 
   bareFrameworks = stdenv.lib.mapAttrs framework (import ./frameworks.nix {

pkgs/os-specific/darwin/apple-sdk/frameworks.nix

@@ -74,6 +74,8 @@ with frameworks; with libs; {
   MediaAccessibility      = [ CF CoreGraphics CoreText QuartzCore ];
   MediaToolbox            = [ AudioToolbox AudioUnit CF CoreMedia ];
   Metal                   = [];
+  MetalKit                = [ ModelIO Metal ];
+  ModelIO                 = [ ];
   NetFS                   = [ CF ];
   OSAKit                  = [ Carbon ];
   OpenAL                  = [];