diff --git a/build/requirements.txt b/build/requirements.txt
index 5e9bbe3..4238770 100644
--- a/build/requirements.txt
+++ b/build/requirements.txt
@@ -3,7 +3,7 @@ arrow==0.13.1
 asn1crypto==0.24.0
 atomicwrites==1.3.0
 attrs==19.1.0
-Babel==2.6.0
+Babel==2.9.1
 backcall==0.1.0
 binaryornot==0.4.4
 bleach==3.1.0