qmk_firmware/keyboards/nullbitsco/nibble/rules.mk

# MCU name
MCU = atmega32u4

# Interrupt driven control endpoint task(+60)
OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT

# Bootloader selection
BOOTLOADER = atmel-dfu

# Build Options
#   change yes to no to disable
#
BOOTMAGIC_ENABLE = no       # Virtual DIP switch configuration
MOUSEKEY_ENABLE = no        # Mouse keys
EXTRAKEY_ENABLE = yes       # Audio control and System control
CONSOLE_ENABLE = no         # Console for debug
COMMAND_ENABLE = no         # Commands for debug and configuration
SLEEP_LED_ENABLE = no       # Breathing sleep LED during USB suspend
NKRO_ENABLE = yes           # USB Nkey Rollover
BACKLIGHT_ENABLE = no       # Enable keyboard backlight functionality
RGBLIGHT_ENABLE = yes       # Enable keyboard RGB underglow
MIDI_ENABLE = no            # MIDI support
BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
AUDIO_ENABLE = no           # Audio output on port C6
FAUXCLICKY_ENABLE = no      # Use buzzer to emulate clicky switches
ENCODER_ENABLE = yes        # Use rotary encoder
LTO_ENABLE = yes            # Link-time optimization
CUSTOM_MATRIX = lite        # Lite custom matrix 

# Project specific files
SRC += matrix.c \
       bitc_led.c \
       big_led.c \
       remote_kb.c \
       tmk_core/common/uart.c