diff --git a/g16ckt/src/circuit/modes/execute_mode.rs b/g16ckt/src/circuit/modes/execute_mode.rs
index d421123..62164b3 100644
--- a/g16ckt/src/circuit/modes/execute_mode.rs
+++ b/g16ckt/src/circuit/modes/execute_mode.rs
@@ -113,7 +113,13 @@ impl CircuitMode for ExecuteMode {
         }
 
         self.storage
-            .set(wire_id, |entry| *entry = Some(value))
+            .set(wire_id, |entry| {
+                assert!(
+                    entry.is_none(),
+                    "overwriting wire_id {wire_id} value in storage"
+                );
+                *entry = Some(value)
+            })
             .unwrap();
     }
 
diff --git a/g16ckt/src/core/gate.rs b/g16ckt/src/core/gate.rs
index 27faf35..05cac8a 100644
--- a/g16ckt/src/core/gate.rs
+++ b/g16ckt/src/core/gate.rs
@@ -133,18 +133,7 @@ impl Gate {
     }
 
     #[must_use]
-    pub fn not(wire_a: &mut WireId) -> Self {
-        let wire_a = *wire_a;
-        Self {
-            wire_a,
-            wire_b: wire_a,
-            wire_c: wire_a,
-            gate_type: GateType::Not,
-        }
-    }
-
-    #[must_use]
-    pub fn not_with_xor(wire_a: WireId, wire_c: WireId) -> Self {
+    pub fn not(wire_a: WireId, wire_c: WireId) -> Self {
         Self {
             wire_a,
             wire_b: TRUE_WIRE,
diff --git a/g16ckt/src/gadgets/basic.rs b/g16ckt/src/gadgets/basic.rs
index c5dbd34..2d58432 100644
--- a/g16ckt/src/gadgets/basic.rs
+++ b/g16ckt/src/gadgets/basic.rs
@@ -117,11 +117,12 @@ mod tests {
             [true],
             10_000,
             |circuit, wire| {
-                let [mut wire] = *wire;
-                circuit.add_gate(Gate::not(&mut wire));
-                circuit.add_gate(Gate::not(&mut wire));
-
-                vec![wire]
+                let [wire] = *wire;
+                let wire_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(wire, wire_not));
+                let wire_not_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(wire_not, wire_not_not));
+                vec![wire_not_not]
             },
         )
         .output_value[0];
@@ -131,12 +132,14 @@ mod tests {
             [true],
             10_000,
             |circuit, wire| {
-                let [mut wire] = *wire;
-                circuit.add_gate(Gate::not(&mut wire));
-                circuit.add_gate(Gate::not(&mut wire));
-                circuit.add_gate(Gate::not(&mut wire));
-
-                vec![wire]
+                let [wire] = *wire;
+                let wire_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(wire, wire_not));
+                let wire_not_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(wire_not, wire_not_not));
+                let wire_not_not_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(wire_not_not, wire_not_not_not));
+                vec![wire_not_not_not]
             },
         )
         .output_value[0];
@@ -150,13 +153,17 @@ mod tests {
             [true, true],
             10_000,
             |circuit, wires| {
-                let [mut a_wire, mut b_wire] = *wires;
+                let [a_wire, b_wire] = *wires;
 
-                circuit.add_gate(Gate::not(&mut a_wire));
-                circuit.add_gate(Gate::not(&mut a_wire));
+                let a_wire_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(a_wire, a_wire_not));
+                let a_wire_not2 = circuit.issue_wire();
+                circuit.add_gate(Gate::not(a_wire_not, a_wire_not2));
 
-                circuit.add_gate(Gate::not(&mut b_wire));
-                circuit.add_gate(Gate::not(&mut b_wire));
+                let b_wire_not = circuit.issue_wire();
+                circuit.add_gate(Gate::not(b_wire, b_wire_not));
+                let b_wire_not2 = circuit.issue_wire();
+                circuit.add_gate(Gate::not(b_wire_not, b_wire_not2));
 
                 let res = circuit.issue_wire();
                 circuit.add_gate(Gate::and(a_wire, b_wire, res));
diff --git a/g16ckt/src/gadgets/bigint/add.rs b/g16ckt/src/gadgets/bigint/add.rs
index 926f136..8e41f34 100644
--- a/g16ckt/src/gadgets/bigint/add.rs
+++ b/g16ckt/src/gadgets/bigint/add.rs
@@ -57,7 +57,7 @@ pub fn add_constant<C: CircuitContext>(
             bits.push(a_i);
         } else if i == first_one {
             let wire = circuit.issue_wire();
-            circuit.add_gate(Gate::not_with_xor(a_i, wire)); //This must be necessary, since the bit is duplicated
+            circuit.add_gate(Gate::not(a_i, wire)); //This must be necessary, since the bit is duplicated
             bits.push(wire);
             carry = Some(a_i);
         } else if b_bits[i] {
diff --git a/g16ckt/src/gadgets/bigint/cmp.rs b/g16ckt/src/gadgets/bigint/cmp.rs
index 12900c9..5ca5bc6 100644
--- a/g16ckt/src/gadgets/bigint/cmp.rs
+++ b/g16ckt/src/gadgets/bigint/cmp.rs
@@ -90,7 +90,7 @@ pub fn equal_zero<C: CircuitContext>(circuit: &mut C, a: &BigIntWires) -> WireId
         let is_bit_zero = circuit.issue_wire();
 
         //this xor might be negated with innate NOT maintenance
-        circuit.add_gate(Gate::not_with_xor(a.get(0).unwrap(), is_bit_zero));
+        circuit.add_gate(Gate::not(a.get(0).unwrap(), is_bit_zero));
 
         return is_bit_zero;
     }
@@ -118,7 +118,7 @@ pub fn greater_than<C: CircuitContext>(
             .map(|b_i| {
                 let w = circuit.issue_wire();
                 //this xor might be negated with innate NOT maintenance
-                circuit.add_gate(Gate::not_with_xor(*b_i, w));
+                circuit.add_gate(Gate::not(*b_i, w));
                 w
             })
             .collect(),
@@ -140,7 +140,7 @@ pub fn less_than_constant<C: CircuitContext>(
             .map(|a_i| {
                 let w = circuit.issue_wire();
                 //this xor might be negated with innate NOT maintenance
-                circuit.add_gate(Gate::not_with_xor(*a_i, w));
+                circuit.add_gate(Gate::not(*a_i, w));
                 w
             })
             .collect(),