diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..68b4e36
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "perception/third_party/sort"]
+	path = perception/third_party/sort
+	url = https://github.com/lawchekun/sort.git
diff --git a/perception/third_party/sort b/perception/third_party/sort
new file mode 160000
index 0000000..517935c
--- /dev/null
+++ b/perception/third_party/sort
@@ -0,0 +1 @@
+Subproject commit 517935cbe088ffc76ebf7e15cd5a6765b2d88bad