diff --git a/circle.yml b/circle.yml
index 4eae4127a725db2312decb72ae40421a97c3ffa2..9c6d84e4af446d6101351aa1b85d0ded0cc67904 100644
--- a/circle.yml
+++ b/circle.yml
@@ -4,7 +4,7 @@ machine:
 
 checkout:
   post:
-    - git submodule sync
+    - git submodule sync --recursive
     - git submodule update --init --recursive
 
 ## Customize dependencies