diff --git a/pkgs/os-specific/darwin/apple-source-releases/default.nix b/pkgs/os-specific/darwin/apple-source-releases/default.nix
index 081c501a5539..978038fc111f 100644
--- a/pkgs/os-specific/darwin/apple-source-releases/default.nix
+++ b/pkgs/os-specific/darwin/apple-source-releases/default.nix
@@ -276,7 +276,9 @@ developerToolsPackages_11_3_1 // macosPackages_11_0_1 // {
     libmalloc       = if stdenv.isx86_64 then
       applePackage "libmalloc" "osx-10.12.6" "sha256-brfG4GEF2yZipKdhlPq6DhT2z5hKYSb2MAmffaikdO4=" {}
     else macosPackages_11_0_1.libmalloc;
-    libplatform     = applePackage "libplatform"       "osx-10.12.6"     "sha256-6McMTjw55xtnCsFI3AB1osRagnuB5pSTqeMKD3gpGtM=" {};
+    libplatform     = if stdenv.isx86_64 then
+      applePackage "libplatform"       "osx-10.12.6"     "sha256-6McMTjw55xtnCsFI3AB1osRagnuB5pSTqeMKD3gpGtM=" {}
+    else macosPackages_11_0_1.libplatform;
     libpthread      = applePackage "libpthread"        "osx-10.12.6"     "sha256-QvJ9PERmrCWBiDmOWrLvQUKZ4JxHuh8gS5nlZKDLqE8=" {};
     libresolv       = applePackage "libresolv"         "osx-10.12.6"     "sha256-FtvwjJKSFX6j9APYPC8WLXVOjbHLZa1Gcoc8yxLy8qE=" {};
     Libsystem       = applePackage "Libsystem"         "osx-10.12.6"     "sha256-zvRdCP//TjKCGAqm/5nJXPppshU1cv2fg/L/yK/olGQ=" {};
diff --git a/pkgs/os-specific/darwin/apple-source-releases/libplatform/default.nix b/pkgs/os-specific/darwin/apple-source-releases/libplatform/default.nix
index 39c801962692..e0b25d27778a 100644
--- a/pkgs/os-specific/darwin/apple-source-releases/libplatform/default.nix
+++ b/pkgs/os-specific/darwin/apple-source-releases/libplatform/default.nix
@@ -1,9 +1,10 @@
-{ appleDerivation', stdenvNoCC }:
+{ lib, appleDerivation', stdenvNoCC }:
 
-appleDerivation' stdenvNoCC {
+appleDerivation' stdenvNoCC (finalAttrs: {
   installPhase = ''
     mkdir $out
     cp -r include $out/include
+    test -d private && cp -r private/* $out/include
   '';
 
   appleHeaders = ''
@@ -27,6 +28,12 @@ appleDerivation' stdenvNoCC {
     platform/introspection_private.h
     platform/string.h
     setjmp.h
-    ucontext.h
-  '';
-}
+  '' + (
+    if lib.versionAtLeast finalAttrs.version "254.40.4" then ''
+      string_x86.h
+      ucontext.h
+    '' else ''
+      ucontext.h
+    ''
+  );
+})