diff --git a/run_once_before_install_brew.sh.tmpl b/run_once_before_install_brew.sh.tmpl
new file mode 100644
index 0000000..f02e8bb
--- /dev/null
+++ b/run_once_before_install_brew.sh.tmpl
@@ -0,0 +1,4 @@
+{{ if eq .chezmoi.os "darwin" -}}
+#!/bin/bash
+/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+{{ end -}}