diff -r 221728aeeb7e -r fa8df5a14486 src/mapping.rs
--- a/src/mapping.rs	Wed Sep 03 19:55:05 2025 -0500
+++ b/src/mapping.rs	Wed Sep 03 20:19:41 2025 -0500
@@ -283,7 +283,7 @@
         // }
 
         self.outer
-            .differential_impl(x.eval_ref_decompose(|r| self.inner.apply(r)))
+            .differential_impl(x.eval_ref(|r| self.inner.apply(r)))
             * self.inner.differential_impl(x)
     }
 }