diff --git a/cabal-install/bootstrap.sh b/cabal-install/bootstrap.sh
index 68934dd12dc..8b79dd60d12 100755
--- a/cabal-install/bootstrap.sh
+++ b/cabal-install/bootstrap.sh
@@ -1,4 +1,5 @@
 #!/bin/sh
+set -e
 
 # A script to bootstrap cabal-install.