diff --git a/goas/atomic_asset_transfer/common/src/lib.rs b/goas/atomic_asset_transfer/common/src/lib.rs
index 2c9e323..dbc18c5 100644
--- a/goas/atomic_asset_transfer/common/src/lib.rs
+++ b/goas/atomic_asset_transfer/common/src/lib.rs
@@ -57,13 +57,11 @@ impl StateWitness {
     ///          /   \        /     \
     ///      events   txs   zoneid  balances
     pub fn commit(&self) -> StateCommitment {
-        let io_root = cl::merkle::node(self.events_root(), self.included_txs_root());
-
         let root = cl::merkle::root([
             self.events_root(),
             self.included_txs_root(),
-            zone_id,
-            balances_root,
+            self.zone_metadata.id(),
+            self.balances_root(),
         ]);
 
         StateCommitment(root)
diff --git a/goas/atomic_asset_transfer/risc0_proofs/spend_zone_funds/src/main.rs b/goas/atomic_asset_transfer/risc0_proofs/spend_zone_funds/src/main.rs
index ab89247..d4b59de 100644
--- a/goas/atomic_asset_transfer/risc0_proofs/spend_zone_funds/src/main.rs
+++ b/goas/atomic_asset_transfer/risc0_proofs/spend_zone_funds/src/main.rs
@@ -75,10 +75,7 @@ fn main() {
     );
     assert_eq!(
         out_zone_funds.output.nonce,
-        in_zone_funds
-            .input
-            .nonce
-            .evolve(&NullifierSecret::from_bytes([0; 16]))
+        in_zone_funds.input.evolved_nonce()
     );
     // the state is propagated
     assert_eq!(
diff --git a/goas/atomic_asset_transfer/risc0_proofs/zone_state/src/main.rs b/goas/atomic_asset_transfer/risc0_proofs/zone_state/src/main.rs
index 29063f8..50216c6 100644
--- a/goas/atomic_asset_transfer/risc0_proofs/zone_state/src/main.rs
+++ b/goas/atomic_asset_transfer/risc0_proofs/zone_state/src/main.rs
@@ -97,12 +97,7 @@ fn deposit(
     assert_eq!(zone_funds_in.nf_sk, NullifierSecret::from_bytes([0; 16])); // there is no secret in the zone funds
     assert_eq!(zone_funds_out.nf_pk, zone_funds_in.nf_sk.commit()); // the sk is the same
                                                                     // nonce is correctly evolved
-    assert_eq!(
-        zone_funds_out.nonce,
-        zone_funds_in
-            .nonce
-            .evolve(&NullifierSecret::from_bytes([0; 16]))
-    );
+    assert_eq!(zone_funds_out.nonce, zone_funds_in.evolved_nonce());
 
     // 5) Check zone state notes are correctly created
     assert_eq!(
@@ -114,12 +109,7 @@ fn deposit(
     assert_eq!(zone_note_in.note.unit, zone_note_out.note.unit);
     assert_eq!(zone_note_in.note.value, zone_note_out.note.value);
     // nonce is correctly evolved
-    assert_eq!(
-        zone_note_out.nonce,
-        zone_note_in
-            .nonce
-            .evolve(&NullifierSecret::from_bytes([0; 16]))
-    );
+    assert_eq!(zone_note_out.nonce, zone_note_in.evolved_nonce());
     let nullifier = Nullifier::new(zone_note_in.nf_sk, zone_note_in.nonce);
     assert_eq!(nullifier, pub_inputs.nf);
 
@@ -167,10 +157,7 @@ fn validate_zone_output(
     assert_eq!(output.note.unit, state.zone_metadata.unit); // the balance unit is the same as in the input
 
     // the nonce is correctly evolved
-    assert_eq!(
-        output.nonce,
-        input.nonce.evolve(&NullifierSecret::from_bytes([0; 16]))
-    );
+    assert_eq!(output.nonce, input.evolved_nonce());
 }
 
 fn main() {
diff --git a/goas/cl/cl/src/input.rs b/goas/cl/cl/src/input.rs
index 17b495c..af056a2 100644
--- a/goas/cl/cl/src/input.rs
+++ b/goas/cl/cl/src/input.rs
@@ -41,13 +41,17 @@ impl InputWitness {
         }
     }
 
+    pub fn evolved_nonce(&self) -> NullifierNonce {
+        self.nonce.evolve(&self.nf_sk)
+    }
+
     pub fn evolve_output(&self, balance_blinding: BalanceWitness) -> crate::OutputWitness {
-	crate::OutputWitness {
-	    note: self.note,
-	    balance_blinding,
-	    nf_pk: self.nf_sk.commit(),
-	    nonce: self.nonce.evolve(&self.nf_sk),
-	}
+        crate::OutputWitness {
+            note: self.note,
+            balance_blinding,
+            nf_pk: self.nf_sk.commit(),
+            nonce: self.evolved_nonce(),
+        }
     }
 
     pub fn nullifier(&self) -> Nullifier {
@@ -63,7 +67,7 @@ impl InputWitness {
     }
 
     pub fn note_commitment(&self) -> crate::NoteCommitment {
-	self.note.commit(self.nf_sk.commit(), self.nonce)
+        self.note.commit(self.nf_sk.commit(), self.nonce)
     }
 }