diff --git a/firmware/Makefile b/firmware/Makefile
index a06d545df9..8a34dd72d6 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -387,6 +387,8 @@ ULIBS = -lm --specs=nano.specs -Wl,--sort-section=alignment
 
 include $(RULESFILE)
 
+include target_sentinel.mk
+
 include rusefi_config.mk
 
 # Enable precompiled header
diff --git a/firmware/bootloader/Makefile b/firmware/bootloader/Makefile
index e798075e3c..4187fddbb6 100644
--- a/firmware/bootloader/Makefile
+++ b/firmware/bootloader/Makefile
@@ -357,6 +357,8 @@ ULIBS = -lm --specs=nano.specs
 
 include $(RULESFILE)
 
+include $(PROJECT_DIR)/target_sentinel.mk
+
 ifneq (yes,$(SUBMAKE))
   include $(PROJECT_DIR)/rusefi_config.mk
 endif
diff --git a/firmware/rusefi_config.mk b/firmware/rusefi_config.mk
index 4dccf82a03..4c396ccd29 100644
--- a/firmware/rusefi_config.mk
+++ b/firmware/rusefi_config.mk
@@ -1,7 +1,5 @@
 include $(PROJECT_DIR)/../java_tools/java_tools.mk
 
-TGT_SENTINEL = $(PROJECT_DIR)/.target-sentinel
-
 # We're assuming that META_OUTPUT_ROOT_FOLDER is a path relative to PROJECT_DIR
 INI_FILE = $(PROJECT_DIR)/$(META_OUTPUT_ROOT_FOLDER)tunerstudio/generated/rusefi_$(SHORT_BOARD_NAME).ini
 SIG_FILE = $(PROJECT_DIR)/tunerstudio/generated/signature_$(SHORT_BOARD_NAME).txt
@@ -46,16 +44,6 @@ $(TCPPOBJS): $(RAMDISK)
 $(SIG_FILE): .FORCE
 	bash $(PROJECT_DIR)/gen_signature.sh $(SHORT_BOARD_NAME)
 
-# This sentinel's purpose is to trigger rebuilds when building for a different target.
-# SHORT_BOARD_NAME doesn't cover all possible changes.
-# For example, if I build Proteus F7, then build Proteus F7 Debug, it won't actually rebuild,
-#  because SHORT_BOARD_NAME hasn't changed. BUNDLE_NAME would be a better specifier,
-#  but it's currently only available from the build_firmware GHA workflow.
-#  Another option would be to use BOARD_META_PATH, and export it in config.sh.
-$(TGT_SENTINEL): .FORCE
-	if [ "$$(cat $@ 2>/dev/null)" != $(SHORT_BOARD_NAME) ]; then \
-	echo $(SHORT_BOARD_NAME) >$@; fi
-
 # Most sentinels are used for multiple targets that are created with a single recipe.
 # In newer versions of GNU Make this is done using the &: operator,
 #  but for supporting older versions, we do it this way.
diff --git a/firmware/target_sentinel.mk b/firmware/target_sentinel.mk
new file mode 100644
index 0000000000..79227480ef
--- /dev/null
+++ b/firmware/target_sentinel.mk
@@ -0,0 +1,13 @@
+TGT_SENTINEL = $(PROJECT_DIR)/.target-sentinel
+
+# This sentinel's purpose is to trigger rebuilds when building for a different target.
+# SHORT_BOARD_NAME doesn't cover all possible changes.
+# For example, if I build Proteus F7, then build Proteus F7 Debug, it won't actually rebuild,
+#  because SHORT_BOARD_NAME hasn't changed. BUNDLE_NAME would be a better specifier,
+#  but it's currently only available from the build_firmware GHA workflow.
+#  Another option would be to use BOARD_META_PATH, and export it in config.sh.
+$(TGT_SENTINEL): .FORCE
+	if [ "$$(cat $@ 2>/dev/null)" != $(SHORT_BOARD_NAME) ]; then \
+	echo $(SHORT_BOARD_NAME) >$@; fi
+
+.FORCE: