diff --git a/build-locally.py b/build-locally.py
index d78427b..8ac9b84 100755
--- a/build-locally.py
+++ b/build-locally.py
@@ -1,8 +1,11 @@
-#!/usr/bin/env python3
+#!/bin/sh
+"""exec' "python3" "$0" "$@" #"""  # fmt: off # fmt: on
 #
 # This file has been generated by conda-smithy in order to build the recipe
 # locally.
 #
+# The line above this comment is a bash / sh / zsh guard
+# to stop people from running it with the wrong interpreter
 import glob
 import os
 import platform