diff --git a/js/ui/main.js b/js/ui/main.js
index 837e5fffb..1f105cb86 100644
--- a/js/ui/main.js
+++ b/js/ui/main.js
@@ -34,6 +34,28 @@ let recorder = null;
 let modalCount = 0;
 let modalActorFocusStack = [];
 
+// "monkey patch" in some varargs ClutterContainer methods; we need
+// to do this per-container class since there is no representation
+// of interfaces in Javascript
+function _patchContainerClass(containerClass) {
+    // This one is a straightforward mapping of the C method
+    containerClass.prototype.child_set = function(actor, props) {
+        let meta = this.get_child_meta(actor);
+        for (prop in props)
+            meta[prop] = props[prop];
+    };
+
+    // clutter_container_add() actually is a an add-many-actors
+    // method. We conveniently, but somewhat dubiously, take the
+    // this opportunity to make it do something more useful.
+    containerClass.prototype.add = function(actor, props) {
+        this.add_actor(actor);
+        if (props)
+            this.child_set(actor, props);
+    };
+}
+_patchContainerClass(Nbtk.BoxLayout);
+
 function start() {
     // Add a binding for "global" in the global JS namespace; (gjs
     // keeps the web browser convention of having that namespace be