diff --git a/Makefile b/Makefile
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@
 
 
 # SOURCES: list of sources in the user application
-SOURCES = main.c usbd_conf.c usbd_cdc_if.c usb_device.c usbd_desc.c stm32f0xx_hal_msp.c stm32f0xx_it.c system_stm32f0xx.c gpio.c spi.c ssd1306.c stringhelpers.c display.c bootlib.c storage.c
+SOURCES = main.c usbd_conf.c usbd_cdc_if.c usb_device.c usbd_desc.c stm32f0xx_hal_msp.c stm32f0xx_it.c system_stm32f0xx.c gpio.c spi.c ssd1306.c stringhelpers.c display.c bootlib.c storage.c flash.c
 
 # TARGET: name of the user application
 TARGET = main