diff --git a/tools/install.sh b/tools/install.sh
index 67d341c7c..dd9c4f842 100755
--- a/tools/install.sh
+++ b/tools/install.sh
@@ -1,3 +1,4 @@
+function main() {
 # Use colors, but only if connected to a terminal, and that terminal
 # supports them.
 tput=$(which tput)
@@ -117,3 +118,6 @@ echo 'p.p.s. Get stickers and t-shirts at http://shop.planetargon.com.'
 echo ''
 printf "${NORMAL}"
 env zsh
+}
+
+main