kmk_firmware/docs/modules.md

Modules

Modules, unlike extensions, change how your keyboard works. These are meant to have the ability to alter the core code in any way. Unlike extensions, these are not in a sandbox, and can make massive changes to normal operation.

Core Modules

These modules are proveded in all builds and can be enabled. Currently offered modules are

• Layers: Adds layer support (Fn key) to allow many more keys to be put on your keyboard
• ModTap: Adds support for augmented modifier keys to act as one key when tapped, and modifier when held.
• Power: Power saving features. This is mostly useful when on battery power.
• Split: Keyboards split in two. Seems ergonomic!