Rat: Compose shell commands to build interactive terminal applications

If it is in $XDG_CONFIG_HOME, why name the file with a leading dot? To me, that's a bit confusing.

Ah, that was my mistake. Thanks!

Emacs Lisp is not a declarative language, of course, but this kind of declarative logic - regular expressions which parse shell command output and apply hidden text properties or keybindings - is common in Emacs. dired does it, as does magit, and all modes based on comint, as well as just normal M-x compile.