diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..cf95759
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "arcanist-extensions"]
+	path = arcanist-extensions
+	url = https://github.com/tagview/arcanist-extensions.git
diff --git a/arcanist-extensions b/arcanist-extensions
new file mode 160000
index 0000000..b89c749
--- /dev/null
+++ b/arcanist-extensions
@@ -0,0 +1 @@
+Subproject commit b89c749a90154676967a1601b62563fed0cbd572