diff --git a/swh/storage/__init__.py b/swh/storage/__init__.py
--- a/swh/storage/__init__.py
+++ b/swh/storage/__init__.py
@@ -34,6 +34,8 @@
         from .api.client import RemoteStorage as Storage
     elif cls == 'local':
         from .storage import Storage
+    elif cls == 'memory':
+        from .in_memory import Storage
     else:
         raise ValueError('Unknown storage class `%s`' % cls)