diff --git a/nion/swift/FacadeQueued.py b/nion/swift/FacadeQueued.py
index <HASH>..<HASH> 100644
--- a/nion/swift/FacadeQueued.py
+++ b/nion/swift/FacadeQueued.py
@@ -2,6 +2,7 @@ import threading
 
 
 all_classes = {
+    "API",
     "Application",
     "DataGroup",
     "DataItem",
Fix Facade method calls on API.