diff --git a/tox.ini b/tox.ini
index b672286ac..021c23949 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@
 
 [tox]
 skipsdist = true
-envlist = modification,py3,py27-cover,lint
+envlist = modification,py3,py27-cover,lint,mypy
 
 [base]
 # pip installs the requested packages in editable mode