diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4e5652a..775a23e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -70,20 +70,20 @@ jobs:
         uses: dtolnay/rust-toolchain@stable
 
       - name: Build halo2 shared library
-        working-directory: zeroj-verifier-halo2/halo2-rust
+        working-directory: incubator/zeroj-verifier-halo2/halo2-rust
         run: cargo build --release
 
       - name: Copy library to resource path
         run: |
-          mkdir -p zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}
-          cp zeroj-verifier-halo2/halo2-rust/target/release/${{ matrix.lib }} \
-             zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
+          mkdir -p incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}
+          cp incubator/zeroj-verifier-halo2/halo2-rust/target/release/${{ matrix.lib }} \
+             incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
 
       - name: Upload native library
         uses: actions/upload-artifact@v4
         with:
           name: halo2-native-${{ matrix.os }}
-          path: zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/${{ matrix.lib }}
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/${{ matrix.lib }}
           retention-days: 1
 
   # ================================================================
@@ -127,26 +127,26 @@ jobs:
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-linux-x86_64
-          path: zeroj-verifier-halo2/src/main/resources/native/linux-x86_64/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/linux-x86_64/
 
       - name: Download halo2 native (linux-arm64)
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-linux-arm64
-          path: zeroj-verifier-halo2/src/main/resources/native/linux-arm64/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/linux-arm64/
 
       - name: Download halo2 native (macos-arm64)
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-macos-arm64
-          path: zeroj-verifier-halo2/src/main/resources/native/macos-arm64/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/macos-arm64/
 
       - name: Verify native libraries are in place
         run: |
           echo "=== gnark native libraries ==="
           find zeroj-prover-gnark/src/main/resources/native -type f
           echo "=== halo2 native libraries ==="
-          find zeroj-verifier-halo2/src/main/resources/native -type f
+          find incubator/zeroj-verifier-halo2/src/main/resources/native -type f
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
@@ -199,7 +199,7 @@ jobs:
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-${{ matrix.os }}
-          path: zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 9334e83..4641444 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -69,20 +69,20 @@ jobs:
         uses: dtolnay/rust-toolchain@stable
 
       - name: Build halo2 shared library
-        working-directory: zeroj-verifier-halo2/halo2-rust
+        working-directory: incubator/zeroj-verifier-halo2/halo2-rust
         run: cargo build --release
 
       - name: Copy library to resource path
         run: |
-          mkdir -p zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}
-          cp zeroj-verifier-halo2/halo2-rust/target/release/${{ matrix.lib }} \
-             zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
+          mkdir -p incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}
+          cp incubator/zeroj-verifier-halo2/halo2-rust/target/release/${{ matrix.lib }} \
+             incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
 
       - name: Upload native library
         uses: actions/upload-artifact@v4
         with:
           name: halo2-native-${{ matrix.os }}
-          path: zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/${{ matrix.lib }}
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/${{ matrix.lib }}
           retention-days: 1
 
   # ================================================================
@@ -125,14 +125,14 @@ jobs:
             cp gnark-native-$platform/* zeroj-prover-gnark/src/main/resources/native/$platform/ || true
 
             # halo2
-            mkdir -p zeroj-verifier-halo2/src/main/resources/native/$platform
-            cp halo2-native-$platform/* zeroj-verifier-halo2/src/main/resources/native/$platform/ || true
+            mkdir -p incubator/zeroj-verifier-halo2/src/main/resources/native/$platform
+            cp halo2-native-$platform/* incubator/zeroj-verifier-halo2/src/main/resources/native/$platform/ || true
           done
 
           echo "=== gnark native libraries ==="
           find zeroj-prover-gnark/src/main/resources/native -type f
           echo "=== halo2 native libraries ==="
-          find zeroj-verifier-halo2/src/main/resources/native -type f
+          find incubator/zeroj-verifier-halo2/src/main/resources/native -type f
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
diff --git a/.github/workflows/snapshot.yml b/.github/workflows/snapshot.yml
index b06d977..bff9fa4 100644
--- a/.github/workflows/snapshot.yml
+++ b/.github/workflows/snapshot.yml
@@ -67,20 +67,20 @@ jobs:
         uses: dtolnay/rust-toolchain@stable
 
       - name: Build halo2 shared library
-        working-directory: zeroj-verifier-halo2/halo2-rust
+        working-directory: incubator/zeroj-verifier-halo2/halo2-rust
         run: cargo build --release
 
       - name: Copy library to resource path
         run: |
-          mkdir -p zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}
-          cp zeroj-verifier-halo2/halo2-rust/target/release/${{ matrix.lib }} \
-             zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
+          mkdir -p incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}
+          cp incubator/zeroj-verifier-halo2/halo2-rust/target/release/${{ matrix.lib }} \
+             incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/
 
       - name: Upload native library
         uses: actions/upload-artifact@v4
         with:
           name: halo2-native-${{ matrix.os }}
-          path: zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/${{ matrix.lib }}
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/${{ matrix.os }}/${{ matrix.lib }}
           retention-days: 1
 
   # ================================================================
@@ -126,26 +126,26 @@ jobs:
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-linux-x86_64
-          path: zeroj-verifier-halo2/src/main/resources/native/linux-x86_64/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/linux-x86_64/
 
       - name: Download halo2 native (linux-arm64)
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-linux-arm64
-          path: zeroj-verifier-halo2/src/main/resources/native/linux-arm64/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/linux-arm64/
 
       - name: Download halo2 native (macos-arm64)
         uses: actions/download-artifact@v4
         with:
           name: halo2-native-macos-arm64
-          path: zeroj-verifier-halo2/src/main/resources/native/macos-arm64/
+          path: incubator/zeroj-verifier-halo2/src/main/resources/native/macos-arm64/
 
       - name: Verify native libraries are in place
         run: |
           echo "=== gnark native libraries ==="
           find zeroj-prover-gnark/src/main/resources/native -type f
           echo "=== halo2 native libraries ==="
-          find zeroj-verifier-halo2/src/main/resources/native -type f
+          find incubator/zeroj-verifier-halo2/src/main/resources/native -type f
 
       - name: Setup Gradle
         uses: gradle/actions/setup-gradle@v4
diff --git a/.gitignore b/.gitignore
index 4672b56..532d021 100644
--- a/.gitignore
+++ b/.gitignore
@@ -62,6 +62,7 @@ zeroj-test-vectors/scripts/build-plonk/
 *.r1cs
 *.sym
 *.ptau
+!zeroj-crypto/src/test/resources/test-circuits/plonk-multiplier/pot8_final.ptau
 
 ### Node.js (circom tooling) ###
 node_modules/
diff --git a/zeroj-api/src/main/java/com/bloxbean/cardano/zeroj/api/R1CSConstraint.java b/zeroj-api/src/main/java/com/bloxbean/cardano/zeroj/api/R1CSConstraint.java
new file mode 100644
index 0000000..17ded01
--- /dev/null
+++ b/zeroj-api/src/main/java/com/bloxbean/cardano/zeroj/api/R1CSConstraint.java
@@ -0,0 +1,16 @@
+package com.bloxbean.cardano.zeroj.api;
+
+import java.math.BigInteger;
+import java.util.Map;
+
+/**
+ * A single R1CS (Rank-1 Constraint System) constraint of the form
+ * {@code (A · w) × (B · w) = (C · w)}, where {@code A}, {@code B}, and
+ * {@code C} are sparse vectors mapping wire indices to field coefficients
+ * and {@code w} is the witness vector.
+ */
+public record R1CSConstraint(
+        Map<Integer, BigInteger> a,
+        Map<Integer, BigInteger> b,
+        Map<Integer, BigInteger> c
+) {}
diff --git a/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSCompiler.java b/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSCompiler.java
index c0a4f88..5438e12 100644
--- a/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSCompiler.java
+++ b/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSCompiler.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.zeroj.circuit.r1cs;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.circuit.*;
 
 import java.math.BigInteger;
@@ -38,7 +39,7 @@ public static R1CSConstraintSystem compile(ConstraintGraph graph, FieldConfig co
             exprMap.put(v.id(), Map.of(v.id(), BigInteger.ONE));
         }
 
-        List<R1CSConstraintSystem.R1CSConstraint> constraints = new ArrayList<>();
+        List<R1CSConstraint> constraints = new ArrayList<>();
 
         for (var gate : graph.gates()) {
             switch (gate) {
@@ -73,7 +74,7 @@ public static R1CSConstraintSystem compile(ConstraintGraph graph, FieldConfig co
                     var a = getExpr(exprMap, left.id());
                     var b = getExpr(exprMap, right.id());
                     var c = Map.of(out.id(), BigInteger.ONE);
-                    constraints.add(new R1CSConstraintSystem.R1CSConstraint(a, b, c));
+                    constraints.add(new R1CSConstraint(a, b, c));
                     // Multiplication output is a new base variable
                     exprMap.put(out.id(), Map.of(out.id(), BigInteger.ONE));
                 }
@@ -84,7 +85,7 @@ public static R1CSConstraintSystem compile(ConstraintGraph graph, FieldConfig co
                     var rightExpr = getExpr(exprMap, right.id());
                     var diff = subExprs(leftExpr, rightExpr, p);
                     if (!diff.isEmpty()) {
-                        constraints.add(new R1CSConstraintSystem.R1CSConstraint(
+                        constraints.add(new R1CSConstraint(
                                 diff,
                                 Map.of(graph.oneWire().id(), BigInteger.ONE),
                                 Map.of() // = 0
diff --git a/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSConstraintSystem.java b/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSConstraintSystem.java
index 92b1356..fe5ac97 100644
--- a/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSConstraintSystem.java
+++ b/zeroj-circuit-dsl/src/main/java/com/bloxbean/cardano/zeroj/circuit/r1cs/R1CSConstraintSystem.java
@@ -1,10 +1,10 @@
 package com.bloxbean.cardano.zeroj.circuit.r1cs;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.circuit.FieldConfig;
 
 import java.math.BigInteger;
 import java.util.List;
-import java.util.Map;
 
 /**
  * A compiled R1CS (Rank-1 Constraint System) for Groth16 proving.
@@ -19,19 +19,6 @@ public record R1CSConstraintSystem(
         int numPrivateInputs,
         List<R1CSConstraint> constraints
 ) {
-    /**
-     * A single R1CS constraint: (A · w) × (B · w) = (C · w).
-     *
-     * @param a sparse vector: wire index → coefficient
-     * @param b sparse vector
-     * @param c sparse vector
-     */
-    public record R1CSConstraint(
-            Map<Integer, BigInteger> a,
-            Map<Integer, BigInteger> b,
-            Map<Integer, BigInteger> c
-    ) {}
-
     public BigInteger prime() { return fieldConfig.prime(); }
     public int numConstraints() { return constraints.size(); }
 }
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16Prover.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16Prover.java
index 1a58663..d8dbdf4 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16Prover.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16Prover.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BN254;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BN254.AffineG1;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BN254;
@@ -10,6 +11,7 @@
 
 import java.math.BigInteger;
 import java.security.SecureRandom;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -47,7 +49,7 @@ private Groth16Prover() {}
     public static Groth16Proof prove(
             Groth16ProvingKey pk,
             BigInteger[] witness,
-            R1CSConstraint[] constraints,
+            List<R1CSConstraint> constraints,
             int numWires) {
         // Domain size = length of H points array in proving key
         int domainSize = pk.pointsH().length;
@@ -57,7 +59,7 @@ public static Groth16Proof prove(
     public static Groth16Proof prove(
             Groth16ProvingKey pk,
             BigInteger[] witness,
-            R1CSConstraint[] constraints,
+            List<R1CSConstraint> constraints,
             int numWires,
             int domainSize) {
 
@@ -82,7 +84,7 @@ public static Groth16Proof prove(
         if (!pk.deltaG2().isOnCurve())
             throw new IllegalArgumentException("Proving key deltaG2 is not on curve");
 
-        int numConstraints = constraints.length;
+        int numConstraints = constraints.size();
 
         // Note: witness validation is available via validateWitness() for R1CS-standard constraints.
         // Not called here because .zkey Section 4 constraints use a different encoding
@@ -102,8 +104,8 @@ public static Groth16Proof prove(
     /** Prove without blinding (r=0, s=0) — for debugging only. */
     static Groth16Proof proveUnblinded(
             Groth16ProvingKey pk, BigInteger[] witness,
-            R1CSConstraint[] constraints, int numWires, int domainSize) {
-        BigInteger[] hCoeffs = computeH(constraints, witness, constraints.length, domainSize);
+            List<R1CSConstraint> constraints, int numWires, int domainSize) {
+        BigInteger[] hCoeffs = computeH(constraints, witness, constraints.size(), domainSize);
         BigInteger r = BigInteger.ZERO;
         BigInteger s = BigInteger.ZERO;
         return proveInternal(pk, witness, hCoeffs, r, s);
@@ -146,7 +148,7 @@ private static Groth16Proof proveInternal(
      * <p>The coset generator is omega_{2n} = the primitive (2*domainSize)-th root of unity,
      * which equals the square root of the domain's omega_n.</p>
      */
-    static BigInteger[] computeH(R1CSConstraint[] constraints, BigInteger[] witness,
+    static BigInteger[] computeH(List<R1CSConstraint> constraints, BigInteger[] witness,
                                   int numConstraints, int domainSize) {
         BigInteger mod = MontFr254.modulus();
         if (domainSize < 2) domainSize = 2;
@@ -156,10 +158,12 @@ static BigInteger[] computeH(R1CSConstraint[] constraints, BigInteger[] witness,
         MontFr254[] aEval = new MontFr254[domainSize];
         MontFr254[] bEval = new MontFr254[domainSize];
 
+        int constraintCount = constraints.size();
         for (int i = 0; i < domainSize; i++) {
-            if (i < numConstraints && i < constraints.length) {
-                aEval[i] = evalLinComb(constraints[i].a(), witness, mod);
-                bEval[i] = evalLinComb(constraints[i].b(), witness, mod);
+            if (i < numConstraints && i < constraintCount) {
+                R1CSConstraint constraint = constraints.get(i);
+                aEval[i] = evalLinComb(constraint.a(), witness, mod);
+                bEval[i] = evalLinComb(constraint.b(), witness, mod);
             } else {
                 aEval[i] = MontFr254.ZERO;
                 bEval[i] = MontFr254.ZERO;
@@ -389,10 +393,10 @@ private static BigInteger randomScalar(SecureRandom rng) {
      * <p>Use this with standard R1CS constraints (from .r1cs files), NOT with .zkey
      * Section 4 constraints which use a different encoding where C is implicit.</p>
      */
-    public static void validateWitness(R1CSConstraint[] constraints, BigInteger[] witness, int numConstraints) {
+    public static void validateWitness(List<R1CSConstraint> constraints, BigInteger[] witness, int numConstraints) {
         BigInteger mod = MontFr254.modulus();
         for (int i = 0; i < numConstraints; i++) {
-            var c = constraints[i];
+            var c = constraints.get(i);
             // Empty constraints (0*0=0) are trivially satisfied — skip
             if (c.a().isEmpty() && c.b().isEmpty() && c.c().isEmpty()) continue;
 
@@ -423,10 +427,4 @@ private static BigInteger evalLCBigInt(Map<Integer, BigInteger> lc, BigInteger[]
         return sum.mod(mod);
     }
 
-    /** R1CS constraint: A · w × B · w = C · w */
-    public record R1CSConstraint(
-            Map<Integer, BigInteger> a,
-            Map<Integer, BigInteger> b,
-            Map<Integer, BigInteger> c
-    ) {}
 }
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverBLS381.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverBLS381.java
index 6f6ddfc..0719b84 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverBLS381.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverBLS381.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381.AffineG1;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381;
@@ -10,6 +11,7 @@
 
 import java.math.BigInteger;
 import java.security.SecureRandom;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -24,7 +26,7 @@ private Groth16ProverBLS381() {}
     public static Groth16ProofBLS381 prove(
             Groth16ProvingKeyBLS381 pk,
             BigInteger[] witness,
-            Groth16Prover.R1CSConstraint[] constraints,
+            List<R1CSConstraint> constraints,
             int numWires) {
         int domainSize = pk.pointsH().length;
         return prove(pk, witness, constraints, numWires, domainSize);
@@ -33,7 +35,7 @@ public static Groth16ProofBLS381 prove(
     public static Groth16ProofBLS381 prove(
             Groth16ProvingKeyBLS381 pk,
             BigInteger[] witness,
-            Groth16Prover.R1CSConstraint[] constraints,
+            List<R1CSConstraint> constraints,
             int numWires,
             int domainSize) {
 
@@ -56,7 +58,7 @@ public static Groth16ProofBLS381 prove(
         if (!pk.deltaG2().isOnCurve())
             throw new IllegalArgumentException("Proving key deltaG2 is not on curve");
 
-        int numConstraints = constraints.length;
+        int numConstraints = constraints.size();
         BigInteger[] hCoeffs = computeH(constraints, witness, numConstraints, domainSize);
 
         var rng = new SecureRandom();
@@ -68,8 +70,8 @@ public static Groth16ProofBLS381 prove(
 
     static Groth16ProofBLS381 proveUnblinded(
             Groth16ProvingKeyBLS381 pk, BigInteger[] witness,
-            Groth16Prover.R1CSConstraint[] constraints, int numWires, int domainSize) {
-        BigInteger[] hCoeffs = computeH(constraints, witness, constraints.length, domainSize);
+            List<R1CSConstraint> constraints, int numWires, int domainSize) {
+        BigInteger[] hCoeffs = computeH(constraints, witness, constraints.size(), domainSize);
         return proveInternal(pk, witness, hCoeffs, BigInteger.ZERO, BigInteger.ZERO);
     }
 
@@ -85,7 +87,7 @@ private static Groth16ProofBLS381 proveInternal(
         return new Groth16ProofBLS381(piA.toAffine(), piB.toAffine(), piC.toAffine());
     }
 
-    static BigInteger[] computeH(Groth16Prover.R1CSConstraint[] constraints, BigInteger[] witness,
+    static BigInteger[] computeH(List<R1CSConstraint> constraints, BigInteger[] witness,
                                   int numConstraints, int domainSize) {
         BigInteger mod = MontFr381.modulus();
         if (domainSize < 2) domainSize = 2;
@@ -94,10 +96,12 @@ static BigInteger[] computeH(Groth16Prover.R1CSConstraint[] constraints, BigInte
         MontFr381[] aEval = new MontFr381[domainSize];
         MontFr381[] bEval = new MontFr381[domainSize];
 
+        int constraintCount = constraints.size();
         for (int i = 0; i < domainSize; i++) {
-            if (i < numConstraints && i < constraints.length) {
-                aEval[i] = evalLinComb(constraints[i].a(), witness, mod);
-                bEval[i] = evalLinComb(constraints[i].b(), witness, mod);
+            if (i < numConstraints && i < constraintCount) {
+                R1CSConstraint constraint = constraints.get(i);
+                aEval[i] = evalLinComb(constraint.a(), witness, mod);
+                bEval[i] = evalLinComb(constraint.b(), witness, mod);
             } else {
                 aEval[i] = MontFr381.ZERO;
                 bEval[i] = MontFr381.ZERO;
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/R1CSImporter.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/R1CSImporter.java
index 98920b1..b59fa1b 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/R1CSImporter.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/R1CSImporter.java
@@ -1,5 +1,7 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
+
 import java.io.IOException;
 import java.io.InputStream;
 import java.math.BigInteger;
@@ -66,12 +68,12 @@ public static R1CSData importR1CS(InputStream input) throws IOException {
 
         // Section 2: Constraints
         buf.position((int) sections.get(2)[0]);
-        var constraints = new Groth16Prover.R1CSConstraint[nConstraints];
+        List<R1CSConstraint> constraints = new ArrayList<>(nConstraints);
         for (int i = 0; i < nConstraints; i++) {
             var a = readLC(buf, n8);
             var b = readLC(buf, n8);
             var c = readLC(buf, n8);
-            constraints[i] = new Groth16Prover.R1CSConstraint(a, b, c);
+            constraints.add(new R1CSConstraint(a, b, c));
         }
 
         return new R1CSData(prime, nWires, nPubOut + nPubIn, nConstraints, constraints);
@@ -102,6 +104,6 @@ public record R1CSData(
             int numWires,
             int numPublic,
             int numConstraints,
-            Groth16Prover.R1CSConstraint[] constraints
+            List<R1CSConstraint> constraints
     ) {}
 }
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyData.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyData.java
index 46c4a58..662739b 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyData.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyData.java
@@ -1,5 +1,9 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
+
+import java.util.List;
+
 /**
  * Complete data from a parsed .zkey file: proving key + R1CS constraints.
  *
@@ -8,7 +12,7 @@
  */
 public record ZkeyData(
         Groth16ProvingKey provingKey,
-        Groth16Prover.R1CSConstraint[] constraints,
+        List<R1CSConstraint> constraints,
         int numConstraints,
         int numWires,
         int domainSize
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyDataBLS381.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyDataBLS381.java
index f7861a1..b384a15 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyDataBLS381.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyDataBLS381.java
@@ -1,11 +1,15 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
+
+import java.util.List;
+
 /**
  * Complete data from a parsed BLS12-381 .zkey file: proving key + R1CS constraints.
  */
 public record ZkeyDataBLS381(
         Groth16ProvingKeyBLS381 provingKey,
-        Groth16Prover.R1CSConstraint[] constraints,
+        List<R1CSConstraint> constraints,
         int numConstraints,
         int numWires,
         int domainSize
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporter.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporter.java
index 811f747..165d7cc 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporter.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporter.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BN254.AffineG1;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BN254.AffineG2;
 import com.bloxbean.cardano.zeroj.crypto.field.MontFp254;
@@ -170,9 +171,9 @@ public static ZkeyData importZkeyFull(byte[] data) throws IOException {
                 actualConstraints = i + 1;
             }
         }
-        var constraints = new Groth16Prover.R1CSConstraint[numConstraints];
+        List<R1CSConstraint> constraints = new ArrayList<>(numConstraints);
         for (int i = 0; i < numConstraints; i++) {
-            constraints[i] = new Groth16Prover.R1CSConstraint(aMap[i], bMap[i], cMap[i]);
+            constraints.add(new R1CSConstraint(aMap[i], bMap[i], cMap[i]));
         }
 
         // Section 5: A points in G1
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporterBLS381.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporterBLS381.java
index d4ca713..4702f50 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporterBLS381.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/groth16/ZkeyImporterBLS381.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381.AffineG1;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381.AffineG2;
 import com.bloxbean.cardano.zeroj.crypto.field.MontFp381;
@@ -146,9 +147,9 @@ public static ZkeyDataBLS381 importZkeyFull(byte[] data) throws IOException {
                 actualConstraints = i + 1;
             }
         }
-        var constraints = new Groth16Prover.R1CSConstraint[numConstraints];
+        List<R1CSConstraint> constraints = new ArrayList<>(numConstraints);
         for (int i = 0; i < numConstraints; i++) {
-            constraints[i] = new Groth16Prover.R1CSConstraint(aMap[i], bMap[i], cMap[i]);
+            constraints.add(new R1CSConstraint(aMap[i], bMap[i], cMap[i]));
         }
 
         // Section 5: A points in G1
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16Setup.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16Setup.java
index dc1ffcb..5e8db55 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16Setup.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16Setup.java
@@ -1,17 +1,18 @@
 package com.bloxbean.cardano.zeroj.crypto.setup;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BN254;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BN254.AffineG1;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BN254;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BN254.AffineG2;
 import com.bloxbean.cardano.zeroj.crypto.field.MontFr254;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProvingKey;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.poly.FieldFFT;
 
 import java.math.BigInteger;
 import java.security.SecureRandom;
 import java.util.Arrays;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -47,14 +48,14 @@ private Groth16Setup() {}
      * @param tau         the toxic waste from PowersOfTau (KNOWN — dev/test only)
      * @return Groth16 proving key ready for Groth16Prover.prove()
      */
-    public static Groth16ProvingKey setup(R1CSConstraint[] constraints, int numWires,
+    public static Groth16ProvingKey setup(List<R1CSConstraint> constraints, int numWires,
                                            int numPublic, BigInteger tau) {
         System.err.println("WARNING: Single-party Groth16 Phase 2 setup — "
                 + "for DEVELOPMENT and TESTING only. "
                 + "Use snarkjs multi-party ceremony for production.");
 
         var rng = new SecureRandom();
-        int nConstraints = constraints.length;
+        int nConstraints = constraints.size();
 
         // Domain size: next power of 2 >= nConstraints
         int domainSize = Integer.highestOneBit(nConstraints);
@@ -104,7 +105,7 @@ public static Groth16ProvingKey setup(R1CSConstraint[] constraints, int numWires
         Arrays.fill(ws, BigInteger.ZERO);
 
         for (int c = 0; c < nConstraints && c < domainSize; c++) {
-            var constraint = constraints[c];
+            var constraint = constraints.get(c);
             BigInteger lc = lagrange[c];
             accumulate(us, constraint.a(), lc);
             accumulate(vs, constraint.b(), lc);
diff --git a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupBLS381.java b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupBLS381.java
index 3374ad8..c75a306 100644
--- a/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupBLS381.java
+++ b/zeroj-crypto/src/main/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupBLS381.java
@@ -1,17 +1,18 @@
 package com.bloxbean.cardano.zeroj.crypto.setup;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381.AffineG1;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381.AffineG2;
 import com.bloxbean.cardano.zeroj.crypto.field.MontFr381;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProvingKeyBLS381;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.poly.FieldFFTBLS381;
 
 import java.math.BigInteger;
 import java.security.SecureRandom;
 import java.util.Arrays;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -47,14 +48,14 @@ private Groth16SetupBLS381() {}
      * @param tau         the toxic waste from PowersOfTauBLS381 (KNOWN — dev/test only)
      * @return Groth16 proving key ready for Groth16ProverBLS381.prove()
      */
-    public static SetupResult setup(R1CSConstraint[] constraints, int numWires,
+    public static SetupResult setup(List<R1CSConstraint> constraints, int numWires,
                                      int numPublic, BigInteger tau) {
         System.err.println("WARNING: Single-party Groth16 Phase 2 setup (BLS12-381) — "
                 + "for DEVELOPMENT and TESTING only. "
                 + "Use snarkjs multi-party ceremony for production.");
 
         var rng = new SecureRandom();
-        int nConstraints = constraints.length;
+        int nConstraints = constraints.size();
 
         // Domain size: next power of 2 >= nConstraints
         int domainSize = Integer.highestOneBit(nConstraints);
@@ -104,7 +105,7 @@ public static SetupResult setup(R1CSConstraint[] constraints, int numWires,
         Arrays.fill(ws, BigInteger.ZERO);
 
         for (int c = 0; c < nConstraints && c < domainSize; c++) {
-            var constraint = constraints[c];
+            var constraint = constraints.get(c);
             BigInteger lc = lagrange[c];
             accumulate(us, constraint.a(), lc);
             accumulate(vs, constraint.b(), lc);
diff --git a/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16BLS381EndToEndTest.java b/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16BLS381EndToEndTest.java
index ad595b4..cf288a0 100644
--- a/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16BLS381EndToEndTest.java
+++ b/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16BLS381EndToEndTest.java
@@ -1,5 +1,6 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
@@ -8,6 +9,7 @@
 import org.junit.jupiter.api.Test;
 
 import java.math.BigInteger;
+import java.util.List;
 import java.util.Map;
 
 import static org.junit.jupiter.api.Assertions.*;
@@ -24,12 +26,12 @@ class Groth16BLS381EndToEndTest {
     void fullPipeline_multiplier_proveAndPairingVerify() {
         // Circuit: c = a * b (multiplier)
         // R1CS: 1 constraint, 4 wires [1, c, a, b]
-        var constraints = new Groth16Prover.R1CSConstraint[]{
-                new Groth16Prover.R1CSConstraint(
+        var constraints = List.of(
+                new R1CSConstraint(
                         Map.of(2, BigInteger.ONE),    // A: wire 2 (a)
                         Map.of(3, BigInteger.ONE),    // B: wire 3 (b)
                         Map.of(1, BigInteger.ONE))    // C: wire 1 (c)
-        };
+        );
         int numWires = 4;
         int numPublic = 1; // wire 1 = c (public output)
 
diff --git a/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverTest.java b/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverTest.java
index fb421ab..ddcefd7 100644
--- a/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverTest.java
+++ b/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/groth16/Groth16ProverTest.java
@@ -1,10 +1,11 @@
 package com.bloxbean.cardano.zeroj.crypto.groth16;
 
+import com.bloxbean.cardano.zeroj.api.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.field.MontFr254;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import org.junit.jupiter.api.Test;
 
 import java.math.BigInteger;
+import java.util.List;
 import java.util.Map;
 
 import static org.junit.jupiter.api.Assertions.*;
@@ -29,7 +30,7 @@ void computeH_multiplierCircuit() {
         // Constraint: (a) * (b) = (product)  → A={2:1}, B={3:1}, C={4:1}
         // assertEqual: (product - c) * 1 = 0 → A={4:1, 1:-1}, B={0:1}, C={}
 
-        var constraints = new R1CSConstraint[]{
+        var constraints = List.of(
                 // a * b = product
                 new R1CSConstraint(
                         Map.of(2, BigInteger.ONE),           // A: wire 2 (a)
@@ -40,7 +41,7 @@ void computeH_multiplierCircuit() {
                         Map.of(4, BigInteger.ONE, 1, R.subtract(BigInteger.ONE)),  // A: product - c
                         Map.of(0, BigInteger.ONE),           // B: 1
                         Map.of())                            // C: 0
-        };
+        );
 
         // Witness: [1, 33, 3, 11, 33]
         BigInteger[] witness = {
@@ -68,12 +69,12 @@ void computeH_multiplierCircuit() {
     @Test
     void computeH_trivialConstraint() {
         // Single constraint: 1 * 1 = 1
-        var constraints = new R1CSConstraint[]{
+        var constraints = List.of(
                 new R1CSConstraint(
                         Map.of(0, BigInteger.ONE),
                         Map.of(0, BigInteger.ONE),
                         Map.of(0, BigInteger.ONE))
-        };
+        );
         BigInteger[] witness = {BigInteger.ONE};
 
         // h(x) should be computable (may be zero polynomial for trivial cases)
@@ -88,19 +89,19 @@ void computeH_adderCircuit() {
         // But we can express it as: (a + b) * 1 = sum
         // Wire 0=1, 1=sum(public), 2=a, 3=b
 
-        var constraints = new R1CSConstraint[]{
+        var constraints = List.of(
                 new R1CSConstraint(
                         Map.of(2, BigInteger.ONE, 3, BigInteger.ONE),  // A: a + b
                         Map.of(0, BigInteger.ONE),                      // B: 1
                         Map.of(1, BigInteger.ONE))                      // C: sum
-        };
+        );
 
         BigInteger[] witness = {BigInteger.ONE, BigInteger.valueOf(15), BigInteger.valueOf(7), BigInteger.valueOf(8)};
 
         // Verify constraint: (7 + 8) * 1 = 15 ✓
-        BigInteger aVal = evalLC(constraints[0].a(), witness);
-        BigInteger bVal = evalLC(constraints[0].b(), witness);
-        BigInteger cVal = evalLC(constraints[0].c(), witness);
+        BigInteger aVal = evalLC(constraints.get(0).a(), witness);
+        BigInteger bVal = evalLC(constraints.get(0).b(), witness);
+        BigInteger cVal = evalLC(constraints.get(0).c(), witness);
         assertEquals(aVal.multiply(bVal).mod(R), cVal);
 
         BigInteger[] h = Groth16Prover.computeH(constraints, witness, 1, 2);
@@ -114,12 +115,12 @@ void computeH_invalidWitness_hNonZeroAtRoots() {
         // that doesn't divide evenly (remainder != 0).
         // We verify this doesn't crash, at minimum.
 
-        var constraints = new R1CSConstraint[]{
+        var constraints = List.of(
                 new R1CSConstraint(
                         Map.of(1, BigInteger.ONE),
                         Map.of(2, BigInteger.ONE),
                         Map.of(3, BigInteger.ONE))
-        };
+        );
 
         // Wrong witness: 3 * 11 != 99
         BigInteger[] witness = {BigInteger.ONE, BigInteger.valueOf(3), BigInteger.valueOf(11), BigInteger.valueOf(99)};
diff --git a/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupTest.java b/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupTest.java
index fbb86df..8267a64 100644
--- a/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupTest.java
+++ b/zeroj-crypto/src/test/java/com/bloxbean/cardano/zeroj/crypto/setup/Groth16SetupTest.java
@@ -3,7 +3,6 @@
 import com.bloxbean.cardano.zeroj.api.CurveId;
 import com.bloxbean.cardano.zeroj.circuit.CircuitBuilder;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.verifier.groth16.bn254.*;
 import org.junit.jupiter.api.Test;
 
@@ -34,9 +33,7 @@ void fullPipeline_multiplier_proveAndVerify() {
         var r1cs = circuit.compileR1CS(CurveId.BN254);
 
         // === Step 4: Convert R1CS constraints to prover format ===
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         // === Step 5: Groth16 Phase 2 setup (pure Java!) ===
         var pk = Groth16Setup.setup(constraints, r1cs.numWires(),
@@ -97,9 +94,7 @@ void setup_provingKeyDimensions() {
                 .define(api -> api.assertEqual(api.add(api.var("a"), api.var("b")), api.var("sum")));
 
         var r1cs = circuit.compileR1CS(CurveId.BN254);
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         var pk = Groth16Setup.setup(constraints, r1cs.numWires(),
                 r1cs.numPublicInputs(), srs.tauScalar());
diff --git a/zeroj-crypto/src/test/resources/test-circuits/plonk-multiplier/pot8_final.ptau b/zeroj-crypto/src/test/resources/test-circuits/plonk-multiplier/pot8_final.ptau
new file mode 100644
index 0000000..8922d19
Binary files /dev/null and b/zeroj-crypto/src/test/resources/test-circuits/plonk-multiplier/pot8_final.ptau differ
diff --git a/zeroj-examples/build.gradle b/zeroj-examples/build.gradle
index 6cfa7c6..578f31e 100644
--- a/zeroj-examples/build.gradle
+++ b/zeroj-examples/build.gradle
@@ -6,7 +6,7 @@ plugins {
 description = 'ZeroJ end-to-end examples and demos'
 
 ext {
-    julcVersion = '0.1.0-pre10-7c66301-SNAPSHOT'
+    julcVersion = '0.1.0-pre11'
     cclVersion = '0.8.0-pre2'
 }
 
diff --git a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/PureJavaProverYaciE2ETest.java b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/PureJavaProverYaciE2ETest.java
index 91995bf..4980562 100644
--- a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/PureJavaProverYaciE2ETest.java
+++ b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/PureJavaProverYaciE2ETest.java
@@ -13,10 +13,9 @@
 import com.bloxbean.cardano.zeroj.api.CurveId;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProverBLS381;
 import com.bloxbean.cardano.zeroj.examples.dsl.multiplier.PrivateMultiplierCircuit;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.PowersOfTauBLS381;
-import com.bloxbean.cardano.zeroj.examples.dsl.common.ProverToCardano;
+import com.bloxbean.cardano.zeroj.onchain.julc.ProverToCardano;
 import com.bloxbean.cardano.zeroj.examples.dsl.common.YaciHelper;
 import com.bloxbean.cardano.zeroj.onchain.julc.Groth16BLS12381Verifier;
 import org.junit.jupiter.api.BeforeAll;
@@ -99,9 +98,7 @@ void pureJavaProve_groth16_onChainVerify() throws Exception {
         var r1cs = circuit.compileR1CS(CurveId.BLS12_381);
         assertEquals(2, r1cs.numPublicInputs(), "Need exactly 2 public inputs for generic verifier");
 
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         // 2. Witness: a=3, b=11, c=33
         BigInteger[] witness = circuit.calculateWitness(Map.of(
diff --git a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/auction/SealedBidPureJavaE2ETest.java b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/auction/SealedBidPureJavaE2ETest.java
index f9aa698..1317fb0 100644
--- a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/auction/SealedBidPureJavaE2ETest.java
+++ b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/auction/SealedBidPureJavaE2ETest.java
@@ -2,7 +2,6 @@
 
 import com.bloxbean.cardano.zeroj.api.CurveId;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProverBLS381;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.PowersOfTauBLS381;
 import com.bloxbean.cardano.zeroj.examples.dsl.common.MiMCHash;
@@ -43,9 +42,7 @@ void devTau_sealedBid_fullStack() {
         // === Step 1: Circuit definition via Java DSL ===
         var circuit = SealedBidCircuit.build();
         var r1cs = circuit.compileR1CS(CurveId.BLS12_381);
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         System.out.println("SealedBid: " + r1cs.numConstraints() + " constraints, "
                 + r1cs.numWires() + " wires");
diff --git a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/balance/BalanceThresholdPureJavaE2ETest.java b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/balance/BalanceThresholdPureJavaE2ETest.java
index e563ca9..9a85a92 100644
--- a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/balance/BalanceThresholdPureJavaE2ETest.java
+++ b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/balance/BalanceThresholdPureJavaE2ETest.java
@@ -2,7 +2,6 @@
 
 import com.bloxbean.cardano.zeroj.api.CurveId;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProverBLS381;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.PowersOfTauBLS381;
 import com.bloxbean.cardano.zeroj.verifier.groth16.bls12381.field.*;
@@ -33,9 +32,7 @@ void devTau_balanceThreshold_fullStack() {
         // === Step 1: Circuit ===
         var circuit = BalanceThresholdCircuit.build();
         var r1cs = circuit.compileR1CS(CurveId.BLS12_381);
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         System.out.println("BalanceThreshold: " + r1cs.numConstraints() + " constraints, "
                 + r1cs.numPublicInputs() + " public inputs");
diff --git a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/templates/ParameterizedCircuitE2ETest.java b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/templates/ParameterizedCircuitE2ETest.java
index 4fa28d6..18ab938 100644
--- a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/templates/ParameterizedCircuitE2ETest.java
+++ b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/templates/ParameterizedCircuitE2ETest.java
@@ -4,7 +4,6 @@
 import com.bloxbean.cardano.zeroj.circuit.CircuitBuilder;
 import com.bloxbean.cardano.zeroj.circuit.FieldConfig;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProverBLS381;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.PowersOfTauBLS381;
 import com.bloxbean.cardano.zeroj.examples.dsl.common.MiMCHash;
@@ -232,9 +231,7 @@ private ProveResult proveMerkle(int depth, NWayMerkleCircuit.HashType hashType)
     private boolean proveAndVerify(CircuitBuilder circuit,
                                     com.bloxbean.cardano.zeroj.circuit.r1cs.R1CSConstraintSystem r1cs,
                                     BigInteger[] witness) {
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         int power = nextPowerOf2Log(r1cs.numConstraints());
         var srs = PowersOfTauBLS381.generate(power);
diff --git a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/voting/AnonymousVotingPureJavaE2ETest.java b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/voting/AnonymousVotingPureJavaE2ETest.java
index 6cfb35f..3d8df97 100644
--- a/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/voting/AnonymousVotingPureJavaE2ETest.java
+++ b/zeroj-examples/src/test/java/com/bloxbean/cardano/zeroj/examples/dsl/voting/AnonymousVotingPureJavaE2ETest.java
@@ -2,7 +2,6 @@
 
 import com.bloxbean.cardano.zeroj.api.CurveId;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProverBLS381;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.PowersOfTauBLS381;
 import com.bloxbean.cardano.zeroj.examples.dsl.common.MiMCHash;
@@ -30,9 +29,7 @@ class AnonymousVotingPureJavaE2ETest {
     void devTau_voteYes_proveAndVerify() {
         var circuit = AnonymousVotingCircuit.build();
         var r1cs = circuit.compileR1CS(CurveId.BLS12_381);
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         System.out.println("AnonymousVoting: " + r1cs.numConstraints() + " constraints");
 
@@ -70,9 +67,7 @@ void devTau_voteYes_proveAndVerify() {
     void devTau_voteNo_proveAndVerify() {
         var circuit = AnonymousVotingCircuit.build();
         var r1cs = circuit.compileR1CS(CurveId.BLS12_381);
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         BigInteger vote = BigInteger.ZERO; // NO
         BigInteger nullifier = BigInteger.valueOf(67890);
diff --git a/zeroj-onchain-julc/build.gradle b/zeroj-onchain-julc/build.gradle
index 3bc719f..b9fe4f1 100644
--- a/zeroj-onchain-julc/build.gradle
+++ b/zeroj-onchain-julc/build.gradle
@@ -22,10 +22,13 @@ dependencies {
     api "com.bloxbean.cardano:julc-stdlib:${julcVersion}"
     annotationProcessor "com.bloxbean.cardano:julc-annotation-processor:${julcVersion}"
 
-    // ZeroJ — blst for point compression in SnarkjsToCardano
+    // ZeroJ — blst for point compression in SnarkjsToCardano / ProverToCardano
     api project(':zeroj-api')
     implementation project(':zeroj-blst')
 
+    // Pure Java prover types — used by ProverToCardano to compress prover output
+    implementation project(':zeroj-crypto')
+
     // JSON parsing for SnarkjsToCardano
     implementation 'com.fasterxml.jackson.core:jackson-databind:2.18.2'
 
@@ -34,8 +37,7 @@ dependencies {
     testImplementation "com.bloxbean.cardano:julc-compiler:${julcVersion}"
     testRuntimeOnly "com.bloxbean.cardano:julc-vm-java:${julcVersion}"
 
-    // Test — pure Java prover for on-chain verification tests
-    testImplementation project(':zeroj-crypto')
+    // Test — circuit DSL for on-chain verification tests
     testImplementation project(':zeroj-circuit-dsl')
 }
 
diff --git a/zeroj-examples/src/main/java/com/bloxbean/cardano/zeroj/examples/dsl/common/ProverToCardano.java b/zeroj-onchain-julc/src/main/java/com/bloxbean/cardano/zeroj/onchain/julc/ProverToCardano.java
similarity index 92%
rename from zeroj-examples/src/main/java/com/bloxbean/cardano/zeroj/examples/dsl/common/ProverToCardano.java
rename to zeroj-onchain-julc/src/main/java/com/bloxbean/cardano/zeroj/onchain/julc/ProverToCardano.java
index daae63c..ed14159 100644
--- a/zeroj-examples/src/main/java/com/bloxbean/cardano/zeroj/examples/dsl/common/ProverToCardano.java
+++ b/zeroj-onchain-julc/src/main/java/com/bloxbean/cardano/zeroj/onchain/julc/ProverToCardano.java
@@ -1,10 +1,9 @@
-package com.bloxbean.cardano.zeroj.examples.dsl.common;
+package com.bloxbean.cardano.zeroj.onchain.julc;
 
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG1BLS381;
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProofBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
-import com.bloxbean.cardano.zeroj.onchain.julc.SnarkjsToCardano;
 import supranational.blst.P1_Affine;
 import supranational.blst.P2_Affine;
 
@@ -16,11 +15,13 @@
  * Converts pure Java BLS12-381 prover output to compressed BLS point bytes
  * suitable for Cardano on-chain use (UPLC BLS12-381 builtins).
  *
- * <p>Bridges zeroj-crypto prover types → zeroj-onchain-julc compressed format.</p>
+ * <p>Bridges {@code zeroj-crypto} prover types to the on-chain Plutus V3
+ * verifier in this module. Sibling of {@link SnarkjsToCardano}, which performs
+ * the same conversion from snarkjs JSON output.</p>
  *
  * <p><b>For production:</b> Use this to convert proofs generated by the pure Java
  * prover ({@code Groth16ProverBLS381}) into the byte format expected by the
- * on-chain Plutus V3 verifier ({@code Groth16BLS12381Verifier}).</p>
+ * on-chain verifier ({@link Groth16BLS12381Verifier}).</p>
  */
 public final class ProverToCardano {
 
diff --git a/zeroj-onchain-julc/src/test/java/com/bloxbean/cardano/zeroj/onchain/julc/Groth16BLS12381PureJavaProverTest.java b/zeroj-onchain-julc/src/test/java/com/bloxbean/cardano/zeroj/onchain/julc/Groth16BLS12381PureJavaProverTest.java
index b9379ab..383bcfd 100644
--- a/zeroj-onchain-julc/src/test/java/com/bloxbean/cardano/zeroj/onchain/julc/Groth16BLS12381PureJavaProverTest.java
+++ b/zeroj-onchain-julc/src/test/java/com/bloxbean/cardano/zeroj/onchain/julc/Groth16BLS12381PureJavaProverTest.java
@@ -6,7 +6,6 @@
 import com.bloxbean.cardano.zeroj.crypto.ec.JacobianG2BLS381;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProverBLS381;
 import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16ProofBLS381;
-import com.bloxbean.cardano.zeroj.crypto.groth16.Groth16Prover.R1CSConstraint;
 import com.bloxbean.cardano.zeroj.crypto.setup.Groth16SetupBLS381;
 import com.bloxbean.cardano.zeroj.crypto.setup.PowersOfTauBLS381;
 import com.bloxbean.cardano.julc.core.PlutusData;
@@ -50,9 +49,7 @@ void twoPublicInputs_pureJavaProve_onChainVerify() {
         var r1cs = circuit.compileR1CS(CurveId.BLS12_381);
         assertEquals(2, r1cs.numPublicInputs(), "Must have exactly 2 public inputs for generic verifier");
 
-        var constraints = r1cs.constraints().stream()
-                .map(c -> new R1CSConstraint(c.a(), c.b(), c.c()))
-                .toArray(R1CSConstraint[]::new);
+        var constraints = r1cs.constraints();
 
         // Witness: a=3, b=11, c=33
         BigInteger[] witness = circuit.calculateWitness(Map.of(