diff --git a/tox.ini b/tox.ini
index 8acbaf8..4255817 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist=py27,py34,py35
+envlist=py27,py34,py35,flake8
 
 [testenv]
 deps=
@@ -8,3 +8,7 @@ deps=
 sitepackages=False
 commands=
     py.test {posargs}
+
+[testenv:flake8]
+deps=flake8
+commands=flake8 django_mailbox