diff --git a/firmware/Makefile b/firmware/Makefile
index a8792977..9a03eca4 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -100,7 +100,7 @@ C_LIBUSB_DFU = dfu.c dfu_desc.c dfu_driver.c
 C_LIBCOMMON  = string.c stdio.c fputs.c usb_buf.c ringbuffer.c pseudo_talloc.c host_communication.c
 
 C_BOARD      = $(notdir $(wildcard libboard/common/source/*.c))
-C_BOARD	    += $(notdir $(wildcard libboard/$(BOARD)/source/*.c))
+C_BOARD     += $(notdir $(wildcard libboard/$(BOARD)/source/*.c))
 
 C_APPLEVEL = $(notdir $(wildcard apps/$(APP)/*.c))