diff --git a/etc/requirements.txt b/etc/requirements.txt
index 6e885296..43af87d8 100644
--- a/etc/requirements.txt
+++ b/etc/requirements.txt
@@ -15,6 +15,8 @@ pandas==0.10.1
 python-dateutil==2.1
 six==1.3.0
 
+# Cython is required for TA-Lib
+Cython==0.19
 TA-Lib==0.4.5
 
 # For fetching remote data