diff --git a/zipline/__init__.py b/zipline/__init__.py
index 4fe138a8..d9516bd6 100644
--- a/zipline/__init__.py
+++ b/zipline/__init__.py
@@ -5,7 +5,7 @@ Zipline
 # This is *not* a place to dump arbitrary classes/modules for convenience,
 # it is a place to expose the public interfaces.
 
-__version__ = 0.5.11.dev
+__version__ = "0.5.11.dev"
 
 from . import data
 from . import finance