diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..47a2764
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "proto"]
+	path = proto
+	url = https://git.kocoder.xyz/vt/proto
diff --git a/proto b/proto
new file mode 160000
index 0000000..880f93b
--- /dev/null
+++ b/proto
@@ -0,0 +1 @@
+Subproject commit 880f93b0ff1a48822f0e261d5f77cdf869790e09