diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000000000000000000000000000000000000..4dd04f3f3585a3d866b674c661051f2aa333c14e
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "workflow/external_repo"]
+	path = workflow/external_repo
+	url = https://git.biohpc.swmed.edu/s219741/astrocyte-atac-runner.git
diff --git a/workflow/external_repo b/workflow/external_repo
new file mode 160000
index 0000000000000000000000000000000000000000..a00c9cffd4efd5c61a1c637afc7ee97231f5c636
--- /dev/null
+++ b/workflow/external_repo
@@ -0,0 +1 @@
+Subproject commit a00c9cffd4efd5c61a1c637afc7ee97231f5c636