diff --git a/.gitmodules b/.gitmodules
index b8ea3f9..9b50b6b 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "src/main/resources/vsrc/vortex"]
 	path = src/main/resources/vsrc/vortex
 	url = https://github.com/hansungk/vortex
+[submodule "radpie"]
+	path = radpie
+	url = git@github.com:hansungk/radpie.git
diff --git a/radpie b/radpie
new file mode 160000
index 0000000..dd9bcec
--- /dev/null
+++ b/radpie
@@ -0,0 +1 @@
+Subproject commit dd9bcec4e3953bf49149e90d64d6a769c1e468e2