Ergonomics

Long Emacs sessions punish the modifier-holding fingers. Protesilaos Stavrou’s keyboard ergonomics writing argues for replacing held modifier chords with one-shot modifiers — tap-then-press — so that the only fingers under load are the ones actually typing characters. Most of Prot’s solution lives in keyboard firmware (split keyboards, QMK one-shot mods, thumb clusters). The Emacs side of the same idea is repeat-mode plus a small set of repeat-maps. This page explains what Jotain enables out of the box, how to extend it, and what to look at next if you want to push further.

Repeat-mode: the Emacs-native one-shot

repeat-mode is built into Emacs 28+ and enabled globally in init-core.el. After running a command tagged with a repeat-map, Emacs installs that map as a transient overlay: the bare trailing keys keep running related commands until you press anything else (or 2 s pass — configured via repeat-exit-timeout). The everyday wins are all built-in:

Type once	Then keep typing	What happens
`M-o`	`o o o`	Cycle through windows
`C-/`	`/ / /`	Undo, undo, undo
`C-x →`	`→ →`	Cycle through buffers
`M-g n`	`n n n`	Jump through compilation errors
`C-x o`	`o O`	`other-window` forward/back

These come from Emacs itself; Jotain just turns the mode on. Run M-x describe-repeat-maps to see every active map at any moment.

Jotain-specific maps

The only built-in command family missing a sensible repeat-map is window resizing. Jotain adds one in lisp/init-keys.el:

(defvar-keymap jotain-window-resize-repeat-map
  :repeat t
  "^" #'enlarge-window
  "v" #'shrink-window
  "}" #'enlarge-window-horizontally
  "{" #'shrink-window-horizontally)

So C-x ^ ^ ^ v overshoots vertically then corrects, and C-x } } } { { widens then narrows horizontally — all without re-pressing C-x. shrink-window has no default key binding, so v only activates inside the repeat overlay (after another entry command has already fired). The 2-second repeat-exit-timeout (in init-core.el) clears the overlay automatically — no C-g needed.

Extending repeat-maps

To add your own, drop a defvar-keymap into lisp/init-keys.el (or the module owning the commands) and tag it with :repeat t. Every command bound in the map gets repeat-map set automatically. For example, paragraph navigation:

(defvar-keymap my-paragraph-repeat-map
  :repeat t
  "{" #'backward-paragraph
  "}" #'forward-paragraph)

Now M-{ { { walks backward through paragraphs without holding Meta.

Pinky-stretch escape hatches Jotain already takes

A few existing bindings are quiet ergonomic wins:

M-o → other-window (instead of C-x o) — one chord, no prefix sequence, both hands involved.
C-z and C-x C-z disabled — removes a foot-gun and frees C-z for personal use.
windmove-default-keybindings — Shift-<arrow> to move directionally between windows, no chord required.
macOS Cmd → Meta (init-core.el) — Meta lives under the thumb, not the pinky.

Beyond Emacs: the rest of Prot’s advice

Most of Prot’s recommendations are outside Emacs’s reach:

Caps Lock → Ctrl is fine, but reinforces left-pinky overuse. Prefer a keyboard with thumb-reachable Ctrl (or remap both sides).
Split keyboards (Prot uses an Iris) let each hand stay in its natural posture and put modifiers under the thumbs.
Firmware one-shot mods (QMK, ZMK) let any key act as a modifier for a single subsequent press. This is the hardware analogue of repeat-mode.

These are out of scope for an Emacs config, but worth knowing about when the in-editor wins above stop being enough.

Optional: `modifier-bar-mode`

Emacs 30 ships modifier-bar-mode, a tool-bar widget that lets you tap Ctrl/Meta/Super/Hyper and have it apply to the next keypress — a clickable one-shot modifier. Jotain disables the tool-bar entirely in early-init.el for a clean UI, so this is off by default. To enable it for yourself, add to your custom.el or a personal init fragment:

(tool-bar-mode 1)
(modifier-bar-mode 1)

Documentation Index

​Ergonomics

​Repeat-mode: the Emacs-native one-shot

​Jotain-specific maps

​Extending repeat-maps

​Pinky-stretch escape hatches Jotain already takes

​Beyond Emacs: the rest of Prot’s advice

​Optional: modifier-bar-mode

​Further reading