Index: setup.py
--- setup.py.orig
+++ setup.py
@@ -1,6 +1,5 @@
 from distutils.core import Extension, setup
 from distutils.command.install import INSTALL_SCHEMES
-from Pyrex.Distutils import build_ext
 import os
 
 # http://stackoverflow.com/questions/1612733/including-non-python-files-with-setup-py
@@ -45,13 +44,8 @@ setup( name='MysticMine',
                 ('monorail/data/music',music),
                 ('monorail/data/snd',snd),
     ],
-    ext_modules=[
-        Extension("monorail.ai", ["monorail/ai.pyx"])
-    ],
-    cmdclass={'build_ext': build_ext},
     requires=[
         "pygame",
         "numpy",
-        "pyrex",
     ],
 )
