diff --git a/targets/stm32l432/Makefile b/targets/stm32l432/Makefile
index 6463634..017998f 100644
--- a/targets/stm32l432/Makefile
+++ b/targets/stm32l432/Makefile
@@ -5,27 +5,27 @@ endif
 merge_hex=python ../../tools/solotool.py mergehex
 
 all:
-	$(MAKE) -f application.mk -j8 solo.hex DEBUG=$(DEBUG) EXTRA_DEFINES='-DFLASH_ROP=1'
+	$(MAKE) -f application.mk -j8 solo.hex PREFIX=$(PREFIX) DEBUG=$(DEBUG) EXTRA_DEFINES='-DFLASH_ROP=1'
 
 all-hacker:
-	$(MAKE) -f application.mk -j8 solo.hex DEBUG=$(DEBUG) EXTRA_DEFINES='-DSOLO_HACKER -DFLASH_ROP=0'
+	$(MAKE) -f application.mk -j8 solo.hex PREFIX=$(PREFIX) DEBUG=$(DEBUG) EXTRA_DEFINES='-DSOLO_HACKER -DFLASH_ROP=0'
 
 all-locked:
-	$(MAKE) -f application.mk -j8 solo.hex EXTRA_DEFINES='-DFLASH_ROP=2'
+	$(MAKE) -f application.mk -j8 solo.hex PREFIX=$(PREFIX) EXTRA_DEFINES='-DFLASH_ROP=2'
 
 debugboot-app:
-	$(MAKE) -f application.mk -j8 solo.hex DEBUG=2 \
+	$(MAKE) -f application.mk -j8 solo.hex DEBUG=2 PREFIX=$(PREFIX)\
 	LDSCRIPT=linker/stm32l4xx_extra.ld EXTRA_DEFINES='-DAPPLICATION_START_PAGE=16 -DSOLO_HACKER'
 
 debugboot-boot:
-	$(MAKE) -f bootloader.mk -j8 bootloader.hex DEBUG=1 \
+	$(MAKE) -f bootloader.mk -j8 bootloader.hex PREFIX=$(PREFIX) DEBUG=1 \
 	LDSCRIPT=linker/bootloader_stm32l4xx_extra.ld EXTRA_DEFINES='-DAPPLICATION_START_PAGE=16 -DSOLO_HACKER'
 
 boot-sig-checking:
-	$(MAKE) -f bootloader.mk -j8 bootloader.hex DEBUG=0
+	$(MAKE) -f bootloader.mk -j8 bootloader.hex PREFIX=$(PREFIX) DEBUG=0
 
 boot-no-sig:
-	$(MAKE) -f bootloader.mk -j8 bootloader.hex EXTRA_DEFINES='-DSOLO_HACKER' DEBUG=0
+	$(MAKE) -f bootloader.mk -j8 bootloader.hex PREFIX=$(PREFIX) EXTRA_DEFINES='-DSOLO_HACKER' DEBUG=0
 
 build-release-locked: clean2 boot-sig-checking clean all-locked
 	$(merge_hex) solo.hex bootloader.hex all.hex
diff --git a/targets/stm32l432/application.mk b/targets/stm32l432/application.mk
index c6b48f4..89ece0d 100644
--- a/targets/stm32l432/application.mk
+++ b/targets/stm32l432/application.mk
@@ -1,7 +1,7 @@
-CC=arm-none-eabi-gcc
-CP=arm-none-eabi-objcopy
-SZ=arm-none-eabi-size
-AR=arm-none-eabi-ar
+CC=$(PREFIX)arm-none-eabi-gcc
+CP=$(PREFIX)arm-none-eabi-objcopy
+SZ=$(PREFIX)arm-none-eabi-size
+AR=$(PREFIX)arm-none-eabi-ar
 
 # ST related
 SRC = src/main.c src/init.c src/redirect.c src/flash.c src/rng.c src/led.c src/device.c
@@ -17,7 +17,6 @@ SRC += ../../fido2/ctap_parse.c ../../fido2/main.c
 # Crypto libs
 SRC += ../../crypto/sha256/sha256.c ../../crypto/micro-ecc/uECC.c ../../crypto/tiny-AES-c/aes.c
 
-
 OBJ1=$(SRC:.c=.o)
 OBJ=$(OBJ1:.s=.o)
 
diff --git a/targets/stm32l432/bootloader.mk b/targets/stm32l432/bootloader.mk
index 4194285..3931dde 100644
--- a/targets/stm32l432/bootloader.mk
+++ b/targets/stm32l432/bootloader.mk
@@ -1,7 +1,7 @@
-CC=arm-none-eabi-gcc
-CP=arm-none-eabi-objcopy
-SZ=arm-none-eabi-size
-AR=arm-none-eabi-ar
+CC=$(PREFIX)arm-none-eabi-gcc
+CP=$(PREFIX)arm-none-eabi-objcopy
+SZ=$(PREFIX)arm-none-eabi-size
+AR=$(PREFIX)arm-none-eabi-ar
 
 # ST related
 SRC = bootloader/main.c bootloader/bootloader.c
@@ -46,7 +46,7 @@ DEFINES = -DDEBUG_LEVEL=$(DEBUG) -D$(CHIP) -DAES256=1  -DUSE_FULL_LL_DRIVER -DAP
 
 CFLAGS=$(INC) -c $(DEFINES)   -Wall -fdata-sections -ffunction-sections $(HW) -g
 LDFLAGS_LIB=$(HW) $(SEARCH) -specs=nano.specs  -specs=nosys.specs  -Wl,--gc-sections  -lnosys
-LDFLAGS=$(HW) $(LDFLAGS_LIB) -T$(LDSCRIPT) -Wl,-Map=$(TARGET).map,--cref  -Wl,-Bstatic
+LDFLAGS=$(HW) $(LDFLAGS_LIB) -T$(LDSCRIPT) -Wl,-Map=$(TARGET).map,--cref  -Wl,-Bstatic 
 
 
 .PRECIOUS: %.o