diff --git a/requirements.txt b/requirements.txt
index f1f26171b..6212ab3cd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,3 +11,4 @@ ujson>=1.35
 dill>=0.2,<0.3
 requests>=2.13.0,<3.0.0
 regex==2017.4.5
+pytest>=3.0.6,<4.0.0