diff --git a/repos/base-hw/lib/mk/core-hw.inc b/repos/base-hw/lib/mk/core-hw.inc
index 8dacf55d10..87cf4dffd5 100644
--- a/repos/base-hw/lib/mk/core-hw.inc
+++ b/repos/base-hw/lib/mk/core-hw.inc
@@ -62,6 +62,7 @@ SRC_CC += capability.cc
 SRC_CC += stack_area_addr.cc
 SRC_CC += heartbeat.cc
 
+BOARD  ?= unknown
 CC_OPT_platform += -DBOARD_NAME="\"$(BOARD)\""
 
 # provide Genode version information
diff --git a/repos/base-hw/recipes/src/base-hw_content.inc b/repos/base-hw/recipes/src/base-hw_content.inc
index 17240b4489..74b6f28336 100644
--- a/repos/base-hw/recipes/src/base-hw_content.inc
+++ b/repos/base-hw/recipes/src/base-hw_content.inc
@@ -200,6 +200,7 @@ generalize_target_names: $(CONTENT)
 	# supplement BOARD definition that normally comes form the build dir
 	sed -i "s/\?= unknown/:= $(BOARD)/" src/core/hw/target.mk
 	sed -i "s/\?= unknown/:= $(BOARD)/" src/bootstrap/hw/target.mk
+	sed -i "s/\?= unknown/:= $(BOARD)/" lib/mk/core-hw.inc
 	# discharge targets when building for mismatching architecture
 	sed -i "1aREQUIRES := $(ARCH)"      src/core/hw/target.mk
 	sed -i "1aREQUIRES     := $(ARCH)"  src/bootstrap/hw/target.mk