From Karabiner Layers to SpaceLauncher

Before SpaceLauncher, I used Karabiner-Elements to build similar keyboard-layer behavior for myself. It was not based on the spacebar at first, but the idea was already there: press one key to enter a layer, then press another key to do something useful.

Karabiner is still excellent at that low level. It can remap Caps Lock, swap modifiers, build a Hyper key, and make different keyboards behave the way you want. It changes what keys are.

SpaceLauncher sits higher up. It is not trying to replace Karabiner’s input-layer remapping. It focuses on one idea: hold Space, type a short sequence, and run an action.

Why Space?

The spacebar is large, central, and already under your thumbs. Most of the time you tap it to type a space. But if the app can tell tap from hold, the same key can become a leader key without taking away normal typing.

That was the reason to make SpaceLauncher. I wanted the keyboard-layer feeling, but tuned around Space as the entry point, with app actions as first-class commands instead of only sending another shortcut.

Where each one fits

Use Karabiner when you want to change keyboard behavior itself:

• You need genuine low-level remapping (Caps Lock → Control, swapping modifiers, per-device rules).
• You want behavior that applies everywhere, including places a normal app can’t reach.
• You’re customizing what individual keys do, not launching actions.

Use SpaceLauncher when you want an action tree:

• Open apps, files, folders, and URLs.
• Run menu items or scripts.
• Simulate a keystroke when that is the right action.
• Group related actions behind prefixes like Space F D for Downloads.

You can use both. Karabiner can handle your low-level keyboard layout, while SpaceLauncher handles the everyday action sequences on top.

Related

Try SpaceLauncher — unlimited trial, $14.99 one-time. See also: how leader keys work.