diff --git a/install-racket.sh b/install-racket.sh
index eb2027a..26e4d56 100644
--- a/install-racket.sh
+++ b/install-racket.sh
@@ -1,3 +1,5 @@
+#!/bin/bash
+
 set -e
 
 if [ "$RACKET_VERSION" == "HEAD" ]; then