Adding Complex Keyboard Modifications via Karabiner as an Emacs Experiment

Drawing Inspiration from Others

I read Enhance Emacs Ergonomics Under X: Happy Hands!; the post provides the following executive summary:

Describes customizations under X that makes my hands happier. Leverages features and (mis-features) of modern-day laptops to break old habits and reduce chording in common cases.

The author uses XCape to overload their Command, Control, and Alt keys.

I was curious about how I might do this in my MacOS setup. I use Karabiner-Elements 📖 for minor modifications. Prior to this post, the only mapping I had was for Left Shift + Right Shift to toggle Caps Lock.

Looking at the Karabiner repository and building from some examples I made the following complex modifications:

  • Left Command pressed alone maps to Left Control + c
  • Left Option pressed alone maps to Left Option + x
  • Left Control pressed alone maps to Left Control + x
  • Right Option pressed alone maps to Right Option + x
  • Right Command pressed alone maps to Right Control + u

Those four modifier keys are the launching point for many of my Emacs 📖 commands. With a bit of practice, we’ll see how this works for me.