diff --git a/experiments/2024-12-09/src/geometry/shape.rs b/experiments/2024-12-09/src/geometry/shape.rs
index 5a775dd11..45b1dd9ac 100644
--- a/experiments/2024-12-09/src/geometry/shape.rs
+++ b/experiments/2024-12-09/src/geometry/shape.rs
@@ -13,6 +13,13 @@ pub struct Shape {
 }
 
 impl Shape {
+    pub fn extend(&mut self) -> OperationResult<()> {
+        OperationResult {
+            operations: self,
+            results: (),
+        }
+    }
+
     pub fn vertex(
         &mut self,
         vertex: impl Into<Vertex>,
diff --git a/experiments/2024-12-09/src/model.rs b/experiments/2024-12-09/src/model.rs
index c3cc9b115..5ffa8cb40 100644
--- a/experiments/2024-12-09/src/model.rs
+++ b/experiments/2024-12-09/src/model.rs
@@ -2,6 +2,7 @@ use crate::geometry::Shape;
 
 pub fn model(shape: &mut Shape) {
     let (a, b, c, d, e, f, g, h) = shape
+        .extend()
         .vertex([-0.5, -0.5, -0.5])
         .vertex([0.5, -0.5, -0.5])
         .vertex([-0.5, 0.5, -0.5])
@@ -13,6 +14,7 @@ pub fn model(shape: &mut Shape) {
         .results();
 
     shape
+        .extend()
         .triangle([&a, &e, &g]) // left
         .triangle([&a, &g, &c])
         .triangle([&b, &d, &h]) // right