diff --git a/deploy.sh b/deploy.sh
index 0117182..0c85afa 100755
--- a/deploy.sh
+++ b/deploy.sh
@@ -1,2 +1,3 @@
-vulcanize -o build.html index.html --strip --inline --csp
+#!/usr/bin/env sh
+exec vulcanize -o build.html index.html --strip --inline --csp
 appcfg.py update . --oauth2