diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..c11dccb
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "tool/github-scripts"]
+    path = tool/github-scripts
+    url = git@github.com:ryo-arima/github-scripts.git
\ No newline at end of file