diff --git a/build_library/build_image_util.sh b/build_library/build_image_util.sh
index c1d3ccb120..90cf6ad05d 100755
--- a/build_library/build_image_util.sh
+++ b/build_library/build_image_util.sh
@@ -104,6 +104,19 @@ emerge_to_image() {
   sudo -E ROOT="${root_fs_dir}" env-update
 }
 
+# Usage: systemd_enable /root default.target something.service
+# Or: systemd_enable /root default.target some@.service some@thing.service
+systemd_enable() {
+  local root_fs_dir="$1"
+  local target="$2"
+  local unit_file="$3"
+  local unit_alias="${4:-$3}"
+  local wants_dir="${root_fs_dir}/usr/lib/systemd/system/${target}.wants"
+
+  sudo mkdir -p "${wants_dir}"
+  sudo ln -sf "../${unit_file}" "${wants_dir}/${unit_alias}"
+}
+
 start_image() {
   local image_name="$1"
   local disk_layout="$2"
diff --git a/build_library/dev_image_util.sh b/build_library/dev_image_util.sh
index cc376d8d85..ec8bddc794 100755
--- a/build_library/dev_image_util.sh
+++ b/build_library/dev_image_util.sh
@@ -94,9 +94,7 @@ EOF
 
   # Remount the system partition read-write by default.
   # The remount services are provided by coreos-base/coreos-init
-  local fs_wants="${root_fs_dir}/usr/lib/systemd/system/local-fs.target.wants"
-  sudo mkdir -p "${fs_wants}"
-  sudo ln -s ../remount-usr.service "${fs_wants}"
+  systemd_enable "${root_fs_dir}" "local-fs.target" "remount-usr.service"
 
   finish_image "${disk_layout}" "${root_fs_dir}" "${update_group}"
 }