diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..26e1bcf
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "swh-loader-git-testdata"]
+	path = swh-loader-git-testdata
+	url = git@git.softwareheritage.org:swh/swh-loader-git-testdata
diff --git a/swh-loader-git-testdata b/swh-loader-git-testdata
new file mode 160000
index 0000000..d566a50
--- /dev/null
+++ b/swh-loader-git-testdata
@@ -0,0 +1 @@
+Subproject commit d566a501787b67450d5545675c9548b5c660c145