Tap and hold

Give one key a tap action and a different hold action.

A key can do one thing when tapped and another when held. The classic turns caps into Escape on tap and Control on hold.

In karabiner.ts

The upstream config wraps toIfAlone in a helper:

export const tapModifier = (v: SideModifierAlias, to: ToEvent) =>
  map(v).to(toKey(v, undefined, { lazy: true })).toIfAlone(to)

In Vimputer

Tap and Hold are moments on one binding, so there’s no helper.

Bind the key

Record caps as a binding’s trigger.

Add the moments

Under Actions, add a Tap moment with a Shortcut of esc, and a Hold moment with ⌃.

Set the hold time

Open Hold and drag its slider. This config uses 200 ms; untouched, Karabiner waits 500 ms.

In the Leader mode, w closes a tab (⌘W) on tap and reopens it (⌘⇧W) on hold:

The Leader layer, with separate Tap and Hold actions on W

To copy the helper’s { lazy: true }, put the modifier on Press instead of Hold and turn on Lazy modifier under the Shortcut’s Key options…. A lazy modifier only applies once another key goes down. See Bindings for every moment.