diff --git a/requirements.txt b/requirements.txt
index 97e0ed9a..0e018854 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,5 +5,6 @@ pymongo
 xlwt
 packaging
 appdirs
-gunicorn
+gunicorn==19.9.0
+pycparser==2.18
 cryptography