1 files changed, 5 insertions, 0 deletions

diff --git a/Prebuild/src/Core/Parse/Preprocessor.cs b/Prebuild/src/Core/Parse/Preprocessor.cs
index c4e1e61..af21090 100644
--- a/Prebuild/src/Core/Parse/Preprocessor.cs
+++ b/Prebuild/src/Core/Parse/Preprocessor.cs
@@ -138,6 +138,11 @@ namespace Prebuild.Core.Parse
                                 return "Win32";
                         }
 
+            if (File.Exists("/System/Library/Frameworks/Cocoa.framework/Cocoa"))
+            {
+                return "MACOSX";
+            }
+
                         /*
                          * .NET 1.x, under Mono, the UNIX code is 128. Under
                          * .NET 2.x, Mono or MS, the UNIX code is 4