diff --git a/requirements.txt b/requirements.txt
index 7d739db1..9fd3dbb0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,6 +10,7 @@ Werkzeug==0.12.1
 alembic==0.9.1
 appdirs==1.4.3
 asn1crypto==0.22.0
+babel==2.5.1
 beautifulsoup4==4.5.3
 cffi==1.9.1
 click==6.7