diff --git a/etc/requirements_dev.txt b/etc/requirements_dev.txt
index f8f61f93..fb1dc736 100644
--- a/etc/requirements_dev.txt
+++ b/etc/requirements_dev.txt
@@ -3,6 +3,7 @@ nose==1.3.0
 nose-parameterized==0.3.3
 nose-ignore-docstring==0.2
 xlrd==0.9.2
+mock=1.0.1
 
 # Linting