diff --git a/setup.py b/setup.py
index a03b536..c112ce1 100644
--- a/setup.py
+++ b/setup.py
@@ -221,7 +221,7 @@ setup(name='cosmotool',
       version='1.0.0a0',
       packages=["cosmotool"],
       package_dir={'cosmotool': 'python/cosmotool'},
-      setup_requires=['cython'],
+      setup_requires=['cython','cffi','numexpr'],
       ext_modules=[CosmoTool_extension],
       description='A small cosmotool box of useful functions',
       long_description=open("./README.md", 'r').read(),