diff --git a/pkgs/development/web/nodejs/nodejs.nix b/pkgs/development/web/nodejs/nodejs.nix
index 0cd80b6cae33..6aaa8db7db18 100644
--- a/pkgs/development/web/nodejs/nodejs.nix
+++ b/pkgs/development/web/nodejs/nodejs.nix
@@ -72,7 +72,6 @@ in
 
     postPatch = ''
       patchShebangs .
-      sed -i 's/raise.*No Xcode or CLT version detected.*/version = "7.0.0"/' tools/gyp/pylib/gyp/xcode_emulation.py
 
       # fix tests
       for a in test/parallel/test-child-process-env.js \
@@ -84,6 +83,7 @@ in
           --replace "/usr/bin/env" "${coreutils}/bin/env"
       done
     '' + optionalString stdenv.isDarwin ''
+      sed -i 's/raise.*No Xcode or CLT version detected.*/version = "7.0.0"/' tools/gyp/pylib/gyp/xcode_emulation.py
       sed -i -e "s|tr1/type_traits|type_traits|g" \
              -e "s|std::tr1|std|" src/util.h
     '';
@@ -101,6 +101,8 @@ in
 
       # install the missing headers for node-gyp
       cp -r ${concatStringsSep " " copyLibHeaders} $out/include/node
+    '' + optionalString (stdenv.isDarwin && enableNpm) ''
+      sed -i 's/raise.*No Xcode or CLT version detected.*/version = "7.0.0"/' $out/lib/node_modules/npm/node_modules/node-gyp/gyp/pylib/gyp/xcode_emulation.py
     '';
 
     passthru.updateScript = import ./update.nix {