Seil

Seil: Open-Source Modifier Key Editor

Seil for macOS allows modification and customization of modifier keys on Apple keyboards, improving keyboard usability.

What is Seil?

Seil is an open-source application for macOS that gives users more control over the modifier keys on Apple keyboards. It allows you to customize the behavior of keys like Caps Lock, Control, Option, and Command in ways that are not normally possible through the standard System Preferences.

Some examples of what you can do with Seil include:
- Change Caps Lock to act as Escape or Control instead
- Swap the Option and Command modifier keys
- Make Caps Lock act as a hyper key to open applications or trigger custom automations
- Set keys to activate macOS keyboard shortcuts like Mission Control or Spotlight search
- Create custom modifier key combinations that can trigger scripts, macros, or other actions

By giving you more flexibility with how modifier keys work, Seil makes it easier to optimize your keyboard layout and shortcuts to match your workflow. It runs quietly in the menu bar and enables custom key behaviors globally across the system.

As an open-source tool, Seil is completely free to use and compatible with most modern Apple keyboards and macOS versions. It provides a GUI for setting up custom key mappings, as well as advanced config options via .reg files for power users. For people wanting more control over their Apple keyboard without buying expensive specialty hardware, Seil is an excellent option.

Seil Features

Official Links