diff --git a/hello_world.py b/hello_world.py
new file mode 100644
index 0000000..ad35e5a
--- /dev/null
+++ b/hello_world.py
@@ -0,0 +1 @@
+print("Hello World")
diff --git a/pseud/auth.py b/pseud/auth.py
index e98f2e7..459a427 100644
--- a/pseud/auth.py
+++ b/pseud/auth.py
@@ -30,6 +30,9 @@ class _BaseAuthBackend:
     def __init__(self, rpc):
         self.rpc = rpc
 
+    async def handle_authentication(self, user_id, routing_id, message_uuid):
+        pass
+
 
 @register_auth_backend
 @zope.interface.implementer(IAuthenticationBackend)
diff --git a/pseud/interfaces.py b/pseud/interfaces.py
index 0fe8d6b..b75b22b 100644
--- a/pseud/interfaces.py
+++ b/pseud/interfaces.py
@@ -57,7 +57,7 @@ async def handle_hello(user_id, routing_id, message_uuid, message):
                                    'Welcome {!r}'.format(user_id)])
         """
 
-    async def handle_authentication(self, user_id, routing_id, message_uuid):
+    async def handle_authentication(user_id, routing_id, message_uuid):
         """
         Called when rpc received acknowledgement of failed authentication.
         """