--- a/setup.py	2014-02-22 22:35:18.000000000 +0100
+++ b/setup.py	2014-03-31 18:02:28.144820932 +0200
@@ -12,6 +12,7 @@
 # limitations under the License.
 import os
 from distutils.command.build import build
+from distutils.command.install import install
 
 from setuptools import setup, find_packages
 
@@ -32,6 +33,27 @@
 ]
 
 
+def get_ext_modules():
+    from cryptography.hazmat.bindings.commoncrypto.binding import (
+        Binding as CommonCryptoBinding
+    )
+    from cryptography.hazmat.bindings.openssl.binding import (
+        Binding as OpenSSLBinding
+    )
+    from cryptography.hazmat.primitives import constant_time, padding
+
+    ext_modules = [
+        OpenSSLBinding().ffi.verifier.get_extension(),
+        constant_time._ffi.verifier.get_extension(),
+        padding._ffi.verifier.get_extension()
+    ]
+    if CommonCryptoBinding.is_available():
+        ext_modules.append(
+            CommonCryptoBinding().ffi.verifier.get_extension()
+        )
+    return ext_modules
+
+
 class cffi_build(build):
     """
     This class exists, instead of just providing ``ext_modules=[...]`` directly
@@ -43,25 +65,17 @@
     """
 
     def finalize_options(self):
-        from cryptography.hazmat.bindings.commoncrypto.binding import (
-            Binding as CommonCryptoBinding
-        )
-        from cryptography.hazmat.bindings.openssl.binding import (
-            Binding as OpenSSLBinding
-        )
-        from cryptography.hazmat.primitives import constant_time, padding
+        self.distribution.ext_modules = get_ext_modules()
+        build.finalize_options(self)
 
-        self.distribution.ext_modules = [
-            OpenSSLBinding().ffi.verifier.get_extension(),
-            constant_time._ffi.verifier.get_extension(),
-            padding._ffi.verifier.get_extension()
-        ]
-        if CommonCryptoBinding.is_available():
-            self.distribution.ext_modules.append(
-                CommonCryptoBinding().ffi.verifier.get_extension()
-            )
 
-        build.finalize_options(self)
+class cffi_install(install):
+    """
+    As a consequence...
+    """
+    def finalize_options(self):
+        self.distribution.ext_modules = get_ext_modules()
+        install.finalize_options(self)
 
 
 with open(os.path.join(base_dir, "README.rst")) as f:
@@ -111,5 +125,6 @@
     ext_package="cryptography",
     cmdclass={
         "build": cffi_build,
+        "install": cffi_install
     }
 )