diff --git a/requirements.txt b/requirements.txt
index 8f8b5f50..5bdf958f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -16,6 +16,7 @@ ipaddress==1.0.14
 itsdangerous==0.24
 Jinja2==2.7.3
 MarkupSafe==0.23
+ndg-httpsclient==0.4.0
 oauth2client==1.5.1
 Pillow==2.8.1
 protobuf==3.0.0a1