use GNU stow for setup

zsh/.zshenv

@@ -0,0 +1,29 @@
+local _old_path="$PATH"
+
+# Local config
+[[ -f ~/.zshenv.local ]] && source ~/.zshenv.local
+
+if [[ $PATH != $_old_path ]]; then
+  # `colors` isn't initialized yet, so define a few manually
+  typeset -AHg fg fg_bold
+  if [ -t 2 ]; then
+    fg[red]=$'\e[31m'
+    fg_bold[white]=$'\e[1;37m'
+    reset_color=$'\e[m'
+  else
+    fg[red]=""
+    fg_bold[white]=""
+    reset_color=""
+  fi
+
+  cat <<MSG >&2
+${fg[red]}Warning:${reset_color} your \`~/.zshenv.local' configuration seems to edit PATH entries.
+Please move that configuration to \`.zshrc.local' like so:
+  ${fg_bold[white]}cat ~/.zshenv.local >> ~/.zshrc.local && rm ~/.zshenv.local${reset_color}
+
+(called from ${(%):-%N:%i})
+
+MSG
+fi
+
+unset _old_path