diff --git a/tox.ini b/tox.ini
index 5caa2b097..90ae81c94 100644
--- a/tox.ini
+++ b/tox.ini
@@ -36,7 +36,7 @@ passenv = OS_*
 commands = python setup.py testr --slowest --testr-args='--concurrency=1 {posargs}'
 
 [testenv:pep8]
-commands = flake8
+commands = flake8 shade
 
 [testenv:venv]
 commands = {posargs}