diff --git a/node.gyp b/node.gyp
index 849b529f8c..3123537545 100644
--- a/node.gyp
+++ b/node.gyp
@@ -178,6 +178,10 @@
         }],
         [ 'OS=="mac"', {
           'libraries': [ '-framework Carbon' ],
+          'defines': [
+            # we need to use node's preferred "darwin" rather than gyp's preferred "mac"
+            'PLATFORM="darwin"',
+          ],
         }],
         [ 'OS=="linux"', {
           'libraries': [