diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 00000000..487a2ae6
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "usb_application/pysim"]
+	path = usb_application/pysim
+	url = git://git.osmocom.org/pysim
diff --git a/usb_application/pysim b/usb_application/pysim
new file mode 160000
index 00000000..2fc205ce
--- /dev/null
+++ b/usb_application/pysim
@@ -0,0 +1 @@
+Subproject commit 2fc205ceb93a8c58d6ad88d3bfd6aa84c628514a