diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 8013dc3..2b641f3 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -7,6 +7,9 @@
 #
 # Copyright 2024 林博仁(Buo-ren Lin) <buo.ren.lin@gmail.com>
 # SPDX-License-Identifier: CC-BY-SA-4.0 OR LicenseRef-Apache-2.0-If-Not-Used-In-Template-Projects
+variables:
+  GIT_SUBMODULE_STRATEGY: recursive
+
 do-static-analysis:
   stage: test
   rules: