-#BOOTMAGIC_ENABLE = yes # Virtual DIP switch configuration(+1000)
-MOUSEKEY_ENABLE = yes # Mouse keys(+4700)
-EXTRAKEY_ENABLE = yes # Audio control and System control(+450)
-CONSOLE_ENABLE = yes # Console for debug(+400)
-COMMAND_ENABLE = yes # Commands for debug and configuration
-#SLEEP_LED_ENABLE = yes # Breathing sleep LED during USB suspend
-#NKRO_ENABLE = yes # USB Nkey Rollover - not yet supported in LUFA
-#KEYMAP_SECTION_ENABLE = yes # fixed address keymap for keymap editor
+#BOOTMAGIC_ENABLE ?= yes # Virtual DIP switch configuration(+1000)
+MOUSEKEY_ENABLE ?= yes # Mouse keys(+4700)
+EXTRAKEY_ENABLE ?= yes # Audio control and System control(+450)
+CONSOLE_ENABLE ?= yes # Console for debug(+400)
+COMMAND_ENABLE ?= yes # Commands for debug and configuration
+#SLEEP_LED_ENABLE ?= yes # Breathing sleep LED during USB suspend
+#NKRO_ENABLE ?= yes # USB Nkey Rollover
+#KEYMAP_SECTION_ENABLE ?= yes # fixed address keymap for keymap editor