diff --git a/build.sh b/build.sh
index f34adfc..054b3f5 100755
--- a/build.sh
+++ b/build.sh
@@ -283,6 +283,7 @@ mkdir -p "${WORK_DIR}"
 log "Begin ${BASE_DIR}"
 
 STAGE_LIST=${STAGE_LIST:-${BASE_DIR}/stage*}
+export STAGE_LIST
 
 for STAGE_DIR in $STAGE_LIST; do
 	STAGE_DIR=$(realpath "${STAGE_DIR}")