You can opt into lexical scope for a script by starting it with: ;; -*- mode: Emacs-Lisp; lexical-binding: t; -*- You can then opt into dynamic scope for si

You can opt into lexical scope for a script by starting it with: ;; -*- mode: Emacs-Lisp; lexical-binding: t; -*- You can then opt into dynamic scope for single variables, when it makes sense: (defvar variable)