diff --git a/docker/hooks/build b/docker/hooks/build
index 618a914..2fee217 100755
--- a/docker/hooks/build
+++ b/docker/hooks/build
@@ -3,6 +3,8 @@
 echo "=> Using custom build hook to add build arguments"
 echo "=> set DEBUG=true to see debug information"
 
+TAG=${DOCKER_TAG:-latest}
+
 if [ "$DEBUG" == "true" ]; then
   env | sort
 fi