diff --git a/circuit/src/ZK/Adder.hs b/circuit/src/ZK/Adder.hs
index 11468cc..f428c68 100644
--- a/circuit/src/ZK/Adder.hs
+++ b/circuit/src/ZK/Adder.hs
@@ -15,14 +15,7 @@ circuit = do
   adder <- var_ <$> fieldInput Private "adder"
   step_in <- map var_ <$> fieldInputs @2 Public "step_in"
   let step_out =
-        bundle_ $
-          Build
-            ( step_in `index` 0
-                + adder
-                  :< step_in
-                  `index` 0
-                + step_in
-                  `index` 1
-                  :< Nil
-            )
-  void $ fieldOutputs "step_out" step_out
+        let so0 = (step_in `index` 0) + adder
+            so1 = (step_in `index` 0) + (step_in `index` 1)
+         in Build (so0 :< so1 :< Nil)
+  void $ fieldOutputs "step_out" (bundle_ step_out)