diff --git a/setup.py b/setup.py
index 34e06d7..0a23c6d 100644
--- a/setup.py
+++ b/setup.py
@@ -40,6 +40,7 @@ setup(name="magic-wormhole",
           "dev": [
               "mock",
               "tox",
+              "pyflakes",
           ],
       },
       test_suite="wormhole.test",