diff --git a/swh/loader/package/py.typed b/swh/loader/package/py.typed
new file mode 100644
index 0000000..1242d43
--- /dev/null
+++ b/swh/loader/package/py.typed
@@ -0,0 +1 @@
+# Marker file for PEP 561.
diff --git a/swh/loader/tests/py.typed b/swh/loader/tests/py.typed
new file mode 100644
index 0000000..1242d43
--- /dev/null
+++ b/swh/loader/tests/py.typed
@@ -0,0 +1 @@
+# Marker file for PEP 561.