qmk-firmware/quantum/template/template.h

#ifndef %KEYBOARD_UPPERCASE%_H
#define %KEYBOARD_UPPERCASE%_H

#include "matrix.h"
#include "keymap_common.h"
#include "backlight.h"
#include <stddef.h>

// This a shortcut to help you visually see your layout.
// The following is an example using the Planck MIT layout
// The first section contains all of the arguements
// The second converts the arguments into a two-dimensional array
#define KEYMAP( \
    k00, k01, k02, \
      k10,  k11   \
) \
{ \
    { k00, k01,   k02 }, \
    { k10, KC_NO, k11 }, \
} 

void matrix_init_user(void);
void matrix_scan_user(void);
void led_set_user(uint8_t usb_led);

#endif