diff --git a/tox.ini b/tox.ini
index 14abfb315..e385f5eec 100644
--- a/tox.ini
+++ b/tox.ini
@@ -31,7 +31,6 @@ setenv = NOSE_WITH_COVERAGE=1
 commands = {posargs}
 
 [flake8]
-builtins = __MARCONI_SETUP__
 exclude = .venv*,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*.egg,.update-venv
 
 [hacking]