diff --git a/firmware/config/boards/f407-discovery/board.mk b/firmware/config/boards/f407-discovery/board.mk
index dbb1b205e9..be50086faa 100644
--- a/firmware/config/boards/f407-discovery/board.mk
+++ b/firmware/config/boards/f407-discovery/board.mk
@@ -10,7 +10,7 @@ endif
 
 # We are running on Frankenso hardware!
 DDEFS += -DHW_FRANKENSO=1
-DDEFS += -DDEFAULT_ENGINE_TYPE=$(DEFAULT_ENGINE_TYPE)
+DDEFS += $(DEFAULT_ENGINE_TYPE)
 
 DDEFS += -DSTM32_I2C_USE_I2C3=TRUE