#! /nix/store/yyy7wr7r9jwjjqkr1yn643g3wzv010zd-bash-4.4-p23/bin/bash case "$1" in bar) echo '/etc/lol/xyz.yaml' ;; baz) echo '/etc/baz.yaml' ;; foo) echo '/etc/foo.yaml' ;; *) echo error: invalid instance >&2 exit 1 ;; esac