diff --git a/circle.yml b/circle.yml
index fa03dd65..b0553fc8 100644
--- a/circle.yml
+++ b/circle.yml
@@ -7,6 +7,10 @@ machine:
         TOX_ENV: py26
         TOX_ENV: py27
 
+checkout:
+    post:
+        - git submodule update --init
+
 dependencies:
     pre:
         - pip install tox