diff --git a/ci/scripts/build.sh b/ci/scripts/build.sh
index 6f559b5ed0..a943aebc23 100755
--- a/ci/scripts/build.sh
+++ b/ci/scripts/build.sh
@@ -28,7 +28,7 @@ _jobs=$(nproc || sysctl -n hw.ncpu)
 jobs="${FDO_CI_CONCURRENT:-$_jobs}"
 
 date -R
-ci/scripts/handle-subprojects-cache.py --cache-dir /subprojects subprojects/
+ci/scripts/handle-subprojects-cache.py --cache-dir "${SUBPROJECTS_CACHE_DIR}" subprojects/
 
 ARGS="${BUILD_TYPE:---default-library=both} ${BUILD_GST_DEBUG:--Dgstreamer:gst_debug=true} ${MESON_ARGS}"
 echo "Werror: $GST_WERROR"