diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.cpp
index 75db931222c..3bafc86f92b 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.cpp
@@ -65,9 +65,6 @@ void build_constraints(Builder& builder, AcirFormat const& constraint_system, bo
     for (const auto& constraint : constraint_system.keccak_constraints) {
         create_keccak_constraints(builder, constraint);
     }
-    for (const auto& constraint : constraint_system.keccak_var_constraints) {
-        create_keccak_var_constraints(builder, constraint);
-    }
     for (const auto& constraint : constraint_system.keccak_permutations) {
         create_keccak_permutations(builder, constraint);
     }
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.hpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.hpp
index c5b64473d80..c91d98c6fcd 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.hpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.hpp
@@ -43,7 +43,6 @@ struct AcirFormat {
     std::vector<Blake2sConstraint> blake2s_constraints;
     std::vector<Blake3Constraint> blake3_constraints;
     std::vector<KeccakConstraint> keccak_constraints;
-    std::vector<KeccakVarConstraint> keccak_var_constraints;
     std::vector<Keccakf1600> keccak_permutations;
     std::vector<PedersenConstraint> pedersen_constraints;
     std::vector<PedersenHashConstraint> pedersen_hash_constraints;
@@ -76,7 +75,6 @@ struct AcirFormat {
                    blake2s_constraints,
                    blake3_constraints,
                    keccak_constraints,
-                   keccak_var_constraints,
                    keccak_permutations,
                    pedersen_constraints,
                    pedersen_hash_constraints,
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.test.cpp
index cf36bbd1c0b..5d2fae4d988 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_format.test.cpp
@@ -43,7 +43,6 @@ TEST_F(AcirFormatTests, TestASingleConstraintNoPubInputs)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -159,7 +158,6 @@ TEST_F(AcirFormatTests, TestLogicGateFromNoirCircuit)
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = {},
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
@@ -227,7 +225,6 @@ TEST_F(AcirFormatTests, TestSchnorrVerifyPass)
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = {},
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
@@ -322,7 +319,6 @@ TEST_F(AcirFormatTests, TestSchnorrVerifySmallRange)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -388,7 +384,7 @@ TEST_F(AcirFormatTests, TestVarKeccak)
     HashInput input3;
     input3.witness = 2;
     input3.num_bits = 8;
-    KeccakVarConstraint keccak;
+    KeccakConstraint keccak;
     keccak.inputs = { input1, input2, input3 };
     keccak.var_message_size = 3;
     keccak.result = { 4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
@@ -435,8 +431,7 @@ TEST_F(AcirFormatTests, TestVarKeccak)
         .ecdsa_r1_constraints = {},
         .blake2s_constraints = {},
         .blake3_constraints = {},
-        .keccak_constraints = {},
-        .keccak_var_constraints = { keccak },
+        .keccak_constraints = { keccak },
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -483,7 +478,6 @@ TEST_F(AcirFormatTests, TestKeccakPermutation)
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = { keccak_permutation },
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_to_constraint_buf.hpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_to_constraint_buf.hpp
index c3b35c2c88c..0034d4cae83 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_to_constraint_buf.hpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/acir_to_constraint_buf.hpp
@@ -244,17 +244,6 @@ void handle_blackbox_func_call(Program::Opcode::BlackBoxFuncCall const& arg, Aci
                                       };
                                   }),
                     .result = map(arg.outputs, [](auto& e) { return e.value; }),
-                });
-            } else if constexpr (std::is_same_v<T, Program::BlackBoxFuncCall::Keccak256VariableLength>) {
-                af.keccak_var_constraints.push_back(KeccakVarConstraint{
-                    .inputs = map(arg.inputs,
-                                  [](auto& e) {
-                                      return HashInput{
-                                          .witness = e.witness.value,
-                                          .num_bits = e.num_bits,
-                                      };
-                                  }),
-                    .result = map(arg.outputs, [](auto& e) { return e.value; }),
                     .var_message_size = arg.var_message_size.witness.value,
                 });
             } else if constexpr (std::is_same_v<T, Program::BlackBoxFuncCall::Keccakf1600>) {
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/bigint_constraint.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/bigint_constraint.test.cpp
index 550ee4a7b40..90d61c52cd5 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/bigint_constraint.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/bigint_constraint.test.cpp
@@ -180,7 +180,6 @@ TEST_F(BigIntTests, TestBigIntConstraintMultiple)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -248,7 +247,6 @@ TEST_F(BigIntTests, TestBigIntConstraintSimple)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -301,7 +299,6 @@ TEST_F(BigIntTests, TestBigIntConstraintReuse)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -358,7 +355,6 @@ TEST_F(BigIntTests, TestBigIntConstraintReuse2)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -436,7 +432,6 @@ TEST_F(BigIntTests, TestBigIntDIV)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -466,4 +461,4 @@ TEST_F(BigIntTests, TestBigIntDIV)
     auto verifier2 = composer.create_ultra_with_keccak_verifier(builder);
     EXPECT_EQ(verifier2.verify_proof(proof), true);
 }
-} // namespace acir_format::tests
\ No newline at end of file
+} // namespace acir_format::tests
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/block_constraint.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/block_constraint.test.cpp
index 3054120b4ba..88d54261ea8 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/block_constraint.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/block_constraint.test.cpp
@@ -122,7 +122,6 @@ TEST_F(UltraPlonkRAM, TestBlockConstraint)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/ec_operations.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/ec_operations.test.cpp
index efcfd7ceace..479d42a2f3c 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/ec_operations.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/ec_operations.test.cpp
@@ -62,7 +62,6 @@ TEST_F(EcOperations, TestECOperations)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256k1.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256k1.test.cpp
index 6d8135cf36f..1986460b53c 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256k1.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256k1.test.cpp
@@ -102,7 +102,6 @@ TEST_F(ECDSASecp256k1, TestECDSAConstraintSucceed)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -151,7 +150,6 @@ TEST_F(ECDSASecp256k1, TestECDSACompilesForVerifier)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -195,7 +193,6 @@ TEST_F(ECDSASecp256k1, TestECDSAConstraintFail)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256r1.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256r1.test.cpp
index 17720a6dd5d..462172d3c4e 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256r1.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/ecdsa_secp256r1.test.cpp
@@ -136,7 +136,6 @@ TEST(ECDSASecp256r1, test_hardcoded)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -187,7 +186,6 @@ TEST(ECDSASecp256r1, TestECDSAConstraintSucceed)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -236,7 +234,6 @@ TEST(ECDSASecp256r1, TestECDSACompilesForVerifier)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
@@ -280,7 +277,6 @@ TEST(ECDSASecp256r1, TestECDSAConstraintFail)
         .blake2s_constraints = {},
         .blake3_constraints = {},
         .keccak_constraints = {},
-        .keccak_var_constraints = {},
         .keccak_permutations = {},
         .pedersen_constraints = {},
         .pedersen_hash_constraints = {},
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.cpp
index 205021739fa..2563204adde 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.cpp
@@ -6,39 +6,6 @@
 namespace acir_format {
 
 template <typename Builder> void create_keccak_constraints(Builder& builder, const KeccakConstraint& constraint)
-{
-    using byte_array_ct = bb::stdlib::byte_array<Builder>;
-    using field_ct = bb::stdlib::field_t<Builder>;
-
-    // Create byte array struct
-    byte_array_ct arr(&builder);
-
-    // Get the witness assignment for each witness index
-    // Write the witness assignment to the byte_array
-    for (const auto& witness_index_num_bits : constraint.inputs) {
-        auto witness_index = witness_index_num_bits.witness;
-        auto num_bits = witness_index_num_bits.num_bits;
-
-        // XXX: The implementation requires us to truncate the element to the nearest byte and not bit
-        auto num_bytes = round_to_nearest_byte(num_bits);
-
-        field_ct element = field_ct::from_witness_index(&builder, witness_index);
-        byte_array_ct element_bytes(element, num_bytes);
-
-        arr.write(element_bytes);
-    }
-
-    byte_array_ct output_bytes = bb::stdlib::keccak<Builder>::hash(arr);
-
-    // Convert byte array to vector of field_t
-    auto bytes = output_bytes.bytes();
-
-    for (size_t i = 0; i < bytes.size(); ++i) {
-        builder.assert_equal(bytes[i].normalize().witness_index, constraint.result[i]);
-    }
-}
-
-template <typename Builder> void create_keccak_var_constraints(Builder& builder, const KeccakVarConstraint& constraint)
 {
     using byte_array_ct = bb::stdlib::byte_array<Builder>;
     using field_ct = bb::stdlib::field_t<Builder>;
@@ -95,15 +62,11 @@ template <typename Builder> void create_keccak_permutations(Builder& builder, co
 }
 template void create_keccak_constraints<UltraCircuitBuilder>(UltraCircuitBuilder& builder,
                                                              const KeccakConstraint& constraint);
-template void create_keccak_var_constraints<UltraCircuitBuilder>(UltraCircuitBuilder& builder,
-                                                                 const KeccakVarConstraint& constraint);
 template void create_keccak_permutations<UltraCircuitBuilder>(UltraCircuitBuilder& builder,
                                                               const Keccakf1600& constraint);
 
 template void create_keccak_constraints<GoblinUltraCircuitBuilder>(GoblinUltraCircuitBuilder& builder,
                                                                    const KeccakConstraint& constraint);
-template void create_keccak_var_constraints<GoblinUltraCircuitBuilder>(GoblinUltraCircuitBuilder& builder,
-                                                                       const KeccakVarConstraint& constraint);
 
 template void create_keccak_permutations<GoblinUltraCircuitBuilder>(GoblinUltraCircuitBuilder& builder,
                                                                     const Keccakf1600& constraint);
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.hpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.hpp
index 4524e35862b..6ce3ccdc5f2 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.hpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/keccak_constraint.hpp
@@ -27,24 +27,14 @@ struct Keccakf1600 {
 struct KeccakConstraint {
     std::vector<HashInput> inputs;
     std::vector<uint32_t> result;
-
-    // For serialization, update with any new fields
-    MSGPACK_FIELDS(inputs, result);
-    friend bool operator==(KeccakConstraint const& lhs, KeccakConstraint const& rhs) = default;
-};
-
-struct KeccakVarConstraint {
-    std::vector<HashInput> inputs;
-    std::vector<uint32_t> result;
     uint32_t var_message_size;
 
     // For serialization, update with any new fields
     MSGPACK_FIELDS(inputs, result, var_message_size);
-    friend bool operator==(KeccakVarConstraint const& lhs, KeccakVarConstraint const& rhs) = default;
+    friend bool operator==(KeccakConstraint const& lhs, KeccakConstraint const& rhs) = default;
 };
 
 template <typename Builder> void create_keccak_constraints(Builder& builder, const KeccakConstraint& constraint);
-template <typename Builder> void create_keccak_var_constraints(Builder& builder, const KeccakVarConstraint& constraint);
 template <typename Builder> void create_keccak_permutations(Builder& builder, const Keccakf1600& constraint);
 
 } // namespace acir_format
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/poseidon2_constraint.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/poseidon2_constraint.test.cpp
index a7b02619734..7ca36a78414 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/poseidon2_constraint.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/poseidon2_constraint.test.cpp
@@ -42,7 +42,6 @@ TEST_F(Poseidon2Tests, TestPoseidon2Permutation)
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = {},
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
@@ -79,4 +78,4 @@ TEST_F(Poseidon2Tests, TestPoseidon2Permutation)
     EXPECT_EQ(verifier.verify_proof(proof), true);
 }
 
-} // namespace acir_format::tests
\ No newline at end of file
+} // namespace acir_format::tests
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/recursion_constraint.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/recursion_constraint.test.cpp
index bc1febd7409..d35e15768fa 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/recursion_constraint.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/recursion_constraint.test.cpp
@@ -94,7 +94,6 @@ Builder create_inner_circuit()
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = {},
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
@@ -251,7 +250,6 @@ Builder create_outer_circuit(std::vector<Builder>& inner_circuits)
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = {},
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/serde/acir.hpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/serde/acir.hpp
index 35db8753546..3e01fd1f155 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/serde/acir.hpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/serde/acir.hpp
@@ -159,6 +159,7 @@ struct BlackBoxFuncCall {
 
     struct Keccak256 {
         std::vector<Program::FunctionInput> inputs;
+        Program::FunctionInput var_message_size;
         std::vector<Program::Witness> outputs;
 
         friend bool operator==(const Keccak256&, const Keccak256&);
@@ -166,16 +167,6 @@ struct BlackBoxFuncCall {
         static Keccak256 bincodeDeserialize(std::vector<uint8_t>);
     };
 
-    struct Keccak256VariableLength {
-        std::vector<Program::FunctionInput> inputs;
-        Program::FunctionInput var_message_size;
-        std::vector<Program::Witness> outputs;
-
-        friend bool operator==(const Keccak256VariableLength&, const Keccak256VariableLength&);
-        std::vector<uint8_t> bincodeSerialize() const;
-        static Keccak256VariableLength bincodeDeserialize(std::vector<uint8_t>);
-    };
-
     struct Keccakf1600 {
         std::vector<Program::FunctionInput> inputs;
         std::vector<Program::Witness> outputs;
@@ -289,7 +280,6 @@ struct BlackBoxFuncCall {
                  FixedBaseScalarMul,
                  EmbeddedCurveAdd,
                  Keccak256,
-                 Keccak256VariableLength,
                  Keccakf1600,
                  RecursiveAggregation,
                  BigIntAdd,
@@ -2954,6 +2944,9 @@ inline bool operator==(const BlackBoxFuncCall::Keccak256& lhs, const BlackBoxFun
     if (!(lhs.inputs == rhs.inputs)) {
         return false;
     }
+    if (!(lhs.var_message_size == rhs.var_message_size)) {
+        return false;
+    }
     if (!(lhs.outputs == rhs.outputs)) {
         return false;
     }
@@ -2985,6 +2978,7 @@ void serde::Serializable<Program::BlackBoxFuncCall::Keccak256>::serialize(
     const Program::BlackBoxFuncCall::Keccak256& obj, Serializer& serializer)
 {
     serde::Serializable<decltype(obj.inputs)>::serialize(obj.inputs, serializer);
+    serde::Serializable<decltype(obj.var_message_size)>::serialize(obj.var_message_size, serializer);
     serde::Serializable<decltype(obj.outputs)>::serialize(obj.outputs, serializer);
 }
 
@@ -2995,64 +2989,6 @@ Program::BlackBoxFuncCall::Keccak256 serde::Deserializable<Program::BlackBoxFunc
 {
     Program::BlackBoxFuncCall::Keccak256 obj;
     obj.inputs = serde::Deserializable<decltype(obj.inputs)>::deserialize(deserializer);
-    obj.outputs = serde::Deserializable<decltype(obj.outputs)>::deserialize(deserializer);
-    return obj;
-}
-
-namespace Program {
-
-inline bool operator==(const BlackBoxFuncCall::Keccak256VariableLength& lhs,
-                       const BlackBoxFuncCall::Keccak256VariableLength& rhs)
-{
-    if (!(lhs.inputs == rhs.inputs)) {
-        return false;
-    }
-    if (!(lhs.var_message_size == rhs.var_message_size)) {
-        return false;
-    }
-    if (!(lhs.outputs == rhs.outputs)) {
-        return false;
-    }
-    return true;
-}
-
-inline std::vector<uint8_t> BlackBoxFuncCall::Keccak256VariableLength::bincodeSerialize() const
-{
-    auto serializer = serde::BincodeSerializer();
-    serde::Serializable<BlackBoxFuncCall::Keccak256VariableLength>::serialize(*this, serializer);
-    return std::move(serializer).bytes();
-}
-
-inline BlackBoxFuncCall::Keccak256VariableLength BlackBoxFuncCall::Keccak256VariableLength::bincodeDeserialize(
-    std::vector<uint8_t> input)
-{
-    auto deserializer = serde::BincodeDeserializer(input);
-    auto value = serde::Deserializable<BlackBoxFuncCall::Keccak256VariableLength>::deserialize(deserializer);
-    if (deserializer.get_buffer_offset() < input.size()) {
-        throw_or_abort("Some input bytes were not read");
-    }
-    return value;
-}
-
-} // end of namespace Program
-
-template <>
-template <typename Serializer>
-void serde::Serializable<Program::BlackBoxFuncCall::Keccak256VariableLength>::serialize(
-    const Program::BlackBoxFuncCall::Keccak256VariableLength& obj, Serializer& serializer)
-{
-    serde::Serializable<decltype(obj.inputs)>::serialize(obj.inputs, serializer);
-    serde::Serializable<decltype(obj.var_message_size)>::serialize(obj.var_message_size, serializer);
-    serde::Serializable<decltype(obj.outputs)>::serialize(obj.outputs, serializer);
-}
-
-template <>
-template <typename Deserializer>
-Program::BlackBoxFuncCall::Keccak256VariableLength serde::Deserializable<
-    Program::BlackBoxFuncCall::Keccak256VariableLength>::deserialize(Deserializer& deserializer)
-{
-    Program::BlackBoxFuncCall::Keccak256VariableLength obj;
-    obj.inputs = serde::Deserializable<decltype(obj.inputs)>::deserialize(deserializer);
     obj.var_message_size = serde::Deserializable<decltype(obj.var_message_size)>::deserialize(deserializer);
     obj.outputs = serde::Deserializable<decltype(obj.outputs)>::deserialize(deserializer);
     return obj;
diff --git a/barretenberg/cpp/src/barretenberg/dsl/acir_format/sha256_constraint.test.cpp b/barretenberg/cpp/src/barretenberg/dsl/acir_format/sha256_constraint.test.cpp
index 037473e31d4..8e770aa4f40 100644
--- a/barretenberg/cpp/src/barretenberg/dsl/acir_format/sha256_constraint.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/dsl/acir_format/sha256_constraint.test.cpp
@@ -44,7 +44,6 @@ TEST_F(Sha256Tests, TestSha256Compression)
                                   .blake2s_constraints = {},
                                   .blake3_constraints = {},
                                   .keccak_constraints = {},
-                                  .keccak_var_constraints = {},
                                   .keccak_permutations = {},
                                   .pedersen_constraints = {},
                                   .pedersen_hash_constraints = {},
@@ -102,4 +101,4 @@ TEST_F(Sha256Tests, TestSha256Compression)
 
     EXPECT_EQ(verifier.verify_proof(proof), true);
 }
-} // namespace acir_format::tests
\ No newline at end of file
+} // namespace acir_format::tests
diff --git a/noir/noir-repo/acvm-repo/acir/codegen/acir.cpp b/noir/noir-repo/acvm-repo/acir/codegen/acir.cpp
index e4203b579b0..7cd9fbefba0 100644
--- a/noir/noir-repo/acvm-repo/acir/codegen/acir.cpp
+++ b/noir/noir-repo/acvm-repo/acir/codegen/acir.cpp
@@ -159,6 +159,7 @@ namespace Program {
 
         struct Keccak256 {
             std::vector<Program::FunctionInput> inputs;
+            Program::FunctionInput var_message_size;
             std::vector<Program::Witness> outputs;
 
             friend bool operator==(const Keccak256&, const Keccak256&);
@@ -166,16 +167,6 @@ namespace Program {
             static Keccak256 bincodeDeserialize(std::vector<uint8_t>);
         };
 
-        struct Keccak256VariableLength {
-            std::vector<Program::FunctionInput> inputs;
-            Program::FunctionInput var_message_size;
-            std::vector<Program::Witness> outputs;
-
-            friend bool operator==(const Keccak256VariableLength&, const Keccak256VariableLength&);
-            std::vector<uint8_t> bincodeSerialize() const;
-            static Keccak256VariableLength bincodeDeserialize(std::vector<uint8_t>);
-        };
-
         struct Keccakf1600 {
             std::vector<Program::FunctionInput> inputs;
             std::vector<Program::Witness> outputs;
@@ -275,7 +266,7 @@ namespace Program {
             static Sha256Compression bincodeDeserialize(std::vector<uint8_t>);
         };
 
-        std::variant<AND, XOR, RANGE, SHA256, Blake2s, Blake3, SchnorrVerify, PedersenCommitment, PedersenHash, EcdsaSecp256k1, EcdsaSecp256r1, FixedBaseScalarMul, EmbeddedCurveAdd, Keccak256, Keccak256VariableLength, Keccakf1600, RecursiveAggregation, BigIntAdd, BigIntSub, BigIntMul, BigIntDiv, BigIntFromLeBytes, BigIntToLeBytes, Poseidon2Permutation, Sha256Compression> value;
+        std::variant<AND, XOR, RANGE, SHA256, Blake2s, Blake3, SchnorrVerify, PedersenCommitment, PedersenHash, EcdsaSecp256k1, EcdsaSecp256r1, FixedBaseScalarMul, EmbeddedCurveAdd, Keccak256, Keccakf1600, RecursiveAggregation, BigIntAdd, BigIntSub, BigIntMul, BigIntDiv, BigIntFromLeBytes, BigIntToLeBytes, Poseidon2Permutation, Sha256Compression> value;
 
         friend bool operator==(const BlackBoxFuncCall&, const BlackBoxFuncCall&);
         std::vector<uint8_t> bincodeSerialize() const;
@@ -2582,6 +2573,7 @@ namespace Program {
 
     inline bool operator==(const BlackBoxFuncCall::Keccak256 &lhs, const BlackBoxFuncCall::Keccak256 &rhs) {
         if (!(lhs.inputs == rhs.inputs)) { return false; }
+        if (!(lhs.var_message_size == rhs.var_message_size)) { return false; }
         if (!(lhs.outputs == rhs.outputs)) { return false; }
         return true;
     }
@@ -2607,6 +2599,7 @@ template <>
 template <typename Serializer>
 void serde::Serializable<Program::BlackBoxFuncCall::Keccak256>::serialize(const Program::BlackBoxFuncCall::Keccak256 &obj, Serializer &serializer) {
     serde::Serializable<decltype(obj.inputs)>::serialize(obj.inputs, serializer);
+    serde::Serializable<decltype(obj.var_message_size)>::serialize(obj.var_message_size, serializer);
     serde::Serializable<decltype(obj.outputs)>::serialize(obj.outputs, serializer);
 }
 
@@ -2615,49 +2608,6 @@ template <typename Deserializer>
 Program::BlackBoxFuncCall::Keccak256 serde::Deserializable<Program::BlackBoxFuncCall::Keccak256>::deserialize(Deserializer &deserializer) {
     Program::BlackBoxFuncCall::Keccak256 obj;
     obj.inputs = serde::Deserializable<decltype(obj.inputs)>::deserialize(deserializer);
-    obj.outputs = serde::Deserializable<decltype(obj.outputs)>::deserialize(deserializer);
-    return obj;
-}
-
-namespace Program {
-
-    inline bool operator==(const BlackBoxFuncCall::Keccak256VariableLength &lhs, const BlackBoxFuncCall::Keccak256VariableLength &rhs) {
-        if (!(lhs.inputs == rhs.inputs)) { return false; }
-        if (!(lhs.var_message_size == rhs.var_message_size)) { return false; }
-        if (!(lhs.outputs == rhs.outputs)) { return false; }
-        return true;
-    }
-
-    inline std::vector<uint8_t> BlackBoxFuncCall::Keccak256VariableLength::bincodeSerialize() const {
-        auto serializer = serde::BincodeSerializer();
-        serde::Serializable<BlackBoxFuncCall::Keccak256VariableLength>::serialize(*this, serializer);
-        return std::move(serializer).bytes();
-    }
-
-    inline BlackBoxFuncCall::Keccak256VariableLength BlackBoxFuncCall::Keccak256VariableLength::bincodeDeserialize(std::vector<uint8_t> input) {
-        auto deserializer = serde::BincodeDeserializer(input);
-        auto value = serde::Deserializable<BlackBoxFuncCall::Keccak256VariableLength>::deserialize(deserializer);
-        if (deserializer.get_buffer_offset() < input.size()) {
-            throw serde::deserialization_error("Some input bytes were not read");
-        }
-        return value;
-    }
-
-} // end of namespace Program
-
-template <>
-template <typename Serializer>
-void serde::Serializable<Program::BlackBoxFuncCall::Keccak256VariableLength>::serialize(const Program::BlackBoxFuncCall::Keccak256VariableLength &obj, Serializer &serializer) {
-    serde::Serializable<decltype(obj.inputs)>::serialize(obj.inputs, serializer);
-    serde::Serializable<decltype(obj.var_message_size)>::serialize(obj.var_message_size, serializer);
-    serde::Serializable<decltype(obj.outputs)>::serialize(obj.outputs, serializer);
-}
-
-template <>
-template <typename Deserializer>
-Program::BlackBoxFuncCall::Keccak256VariableLength serde::Deserializable<Program::BlackBoxFuncCall::Keccak256VariableLength>::deserialize(Deserializer &deserializer) {
-    Program::BlackBoxFuncCall::Keccak256VariableLength obj;
-    obj.inputs = serde::Deserializable<decltype(obj.inputs)>::deserialize(deserializer);
     obj.var_message_size = serde::Deserializable<decltype(obj.var_message_size)>::deserialize(deserializer);
     obj.outputs = serde::Deserializable<decltype(obj.outputs)>::deserialize(deserializer);
     return obj;
diff --git a/noir/noir-repo/acvm-repo/acir/src/circuit/opcodes/black_box_function_call.rs b/noir/noir-repo/acvm-repo/acir/src/circuit/opcodes/black_box_function_call.rs
index c955e435b37..d9089578739 100644
--- a/noir/noir-repo/acvm-repo/acir/src/circuit/opcodes/black_box_function_call.rs
+++ b/noir/noir-repo/acvm-repo/acir/src/circuit/opcodes/black_box_function_call.rs
@@ -81,10 +81,6 @@ pub enum BlackBoxFuncCall {
         outputs: (Witness, Witness),
     },
     Keccak256 {
-        inputs: Vec<FunctionInput>,
-        outputs: Vec<Witness>,
-    },
-    Keccak256VariableLength {
         inputs: Vec<FunctionInput>,
         /// This is the number of bytes to take
         /// from the input. Note: if `var_message_size`
@@ -183,7 +179,6 @@ impl BlackBoxFuncCall {
             BlackBoxFuncCall::FixedBaseScalarMul { .. } => BlackBoxFunc::FixedBaseScalarMul,
             BlackBoxFuncCall::EmbeddedCurveAdd { .. } => BlackBoxFunc::EmbeddedCurveAdd,
             BlackBoxFuncCall::Keccak256 { .. } => BlackBoxFunc::Keccak256,
-            BlackBoxFuncCall::Keccak256VariableLength { .. } => BlackBoxFunc::Keccak256,
             BlackBoxFuncCall::Keccakf1600 { .. } => BlackBoxFunc::Keccakf1600,
             BlackBoxFuncCall::RecursiveAggregation { .. } => BlackBoxFunc::RecursiveAggregation,
             BlackBoxFuncCall::BigIntAdd { .. } => BlackBoxFunc::BigIntAdd,
@@ -206,7 +201,6 @@ impl BlackBoxFuncCall {
             BlackBoxFuncCall::SHA256 { inputs, .. }
             | BlackBoxFuncCall::Blake2s { inputs, .. }
             | BlackBoxFuncCall::Blake3 { inputs, .. }
-            | BlackBoxFuncCall::Keccak256 { inputs, .. }
             | BlackBoxFuncCall::Keccakf1600 { inputs, .. }
             | BlackBoxFuncCall::PedersenCommitment { inputs, .. }
             | BlackBoxFuncCall::PedersenHash { inputs, .. }
@@ -280,7 +274,7 @@ impl BlackBoxFuncCall {
                 inputs.extend(hashed_message.iter().copied());
                 inputs
             }
-            BlackBoxFuncCall::Keccak256VariableLength { inputs, var_message_size, .. } => {
+            BlackBoxFuncCall::Keccak256 { inputs, var_message_size, .. } => {
                 let mut inputs = inputs.clone();
                 inputs.push(*var_message_size);
                 inputs
@@ -306,9 +300,8 @@ impl BlackBoxFuncCall {
             BlackBoxFuncCall::SHA256 { outputs, .. }
             | BlackBoxFuncCall::Blake2s { outputs, .. }
             | BlackBoxFuncCall::Blake3 { outputs, .. }
-            | BlackBoxFuncCall::Keccak256 { outputs, .. }
             | BlackBoxFuncCall::Keccakf1600 { outputs, .. }
-            | BlackBoxFuncCall::Keccak256VariableLength { outputs, .. }
+            | BlackBoxFuncCall::Keccak256 { outputs, .. }
             | BlackBoxFuncCall::Poseidon2Permutation { outputs, .. }
             | BlackBoxFuncCall::Sha256Compression { outputs, .. } => outputs.to_vec(),
             BlackBoxFuncCall::AND { output, .. }
diff --git a/noir/noir-repo/acvm-repo/acvm/src/pwg/blackbox/mod.rs b/noir/noir-repo/acvm-repo/acvm/src/pwg/blackbox/mod.rs
index 6ee926043cd..e7ed402a8eb 100644
--- a/noir/noir-repo/acvm-repo/acvm/src/pwg/blackbox/mod.rs
+++ b/noir/noir-repo/acvm-repo/acvm/src/pwg/blackbox/mod.rs
@@ -95,15 +95,7 @@ pub(crate) fn solve(
             blake3,
             bb_func.get_black_box_func(),
         ),
-        BlackBoxFuncCall::Keccak256 { inputs, outputs } => solve_generic_256_hash_opcode(
-            initial_witness,
-            inputs,
-            None,
-            outputs,
-            keccak256,
-            bb_func.get_black_box_func(),
-        ),
-        BlackBoxFuncCall::Keccak256VariableLength { inputs, var_message_size, outputs } => {
+        BlackBoxFuncCall::Keccak256 { inputs, var_message_size, outputs } => {
             solve_generic_256_hash_opcode(
                 initial_witness,
                 inputs,
diff --git a/noir/noir-repo/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/generated_acir.rs b/noir/noir-repo/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/generated_acir.rs
index b43110b2f5b..ba4e03bff95 100644
--- a/noir/noir-repo/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/generated_acir.rs
+++ b/noir/noir-repo/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/generated_acir.rs
@@ -240,11 +240,7 @@ impl GeneratedAcir {
                     }
                 };
 
-                BlackBoxFuncCall::Keccak256VariableLength {
-                    inputs: inputs[0].clone(),
-                    var_message_size,
-                    outputs,
-                }
+                BlackBoxFuncCall::Keccak256 { inputs: inputs[0].clone(), var_message_size, outputs }
             }
             BlackBoxFunc::Keccakf1600 => {
                 BlackBoxFuncCall::Keccakf1600 { inputs: inputs[0].clone(), outputs }
diff --git a/noir/noir-repo/tooling/noir_js_backend_barretenberg/package.json b/noir/noir-repo/tooling/noir_js_backend_barretenberg/package.json
index 251dd80c2f4..1ea384cdd49 100644
--- a/noir/noir-repo/tooling/noir_js_backend_barretenberg/package.json
+++ b/noir/noir-repo/tooling/noir_js_backend_barretenberg/package.json
@@ -42,7 +42,7 @@
     "lint": "NODE_NO_WARNINGS=1 eslint . --ext .ts --ignore-path ./.eslintignore  --max-warnings 0"
   },
   "dependencies": {
-    "@aztec/bb.js": "0.32.0",
+    "@aztec/bb.js": "portal:../../../../barretenberg/ts",
     "@noir-lang/types": "workspace:*",
     "fflate": "^0.8.0"
   },
diff --git a/noir/noir-repo/yarn.lock b/noir/noir-repo/yarn.lock
index a39ae9921da..b45678f5d8b 100644
--- a/noir/noir-repo/yarn.lock
+++ b/noir/noir-repo/yarn.lock
@@ -221,19 +221,18 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@aztec/bb.js@npm:0.32.0":
-  version: 0.32.0
-  resolution: "@aztec/bb.js@npm:0.32.0"
+"@aztec/bb.js@portal:../../../../barretenberg/ts::locator=%40noir-lang%2Fbackend_barretenberg%40workspace%3Atooling%2Fnoir_js_backend_barretenberg":
+  version: 0.0.0-use.local
+  resolution: "@aztec/bb.js@portal:../../../../barretenberg/ts::locator=%40noir-lang%2Fbackend_barretenberg%40workspace%3Atooling%2Fnoir_js_backend_barretenberg"
   dependencies:
     comlink: ^4.4.1
     commander: ^10.0.1
     debug: ^4.3.4
     tslib: ^2.4.0
   bin:
-    bb.js: dest/node/main.js
-  checksum: 0919957e141ae0a65cfab961dce122fa06de628a10b7cb661d31d8ed4793ce80980fcf315620ceffffa45581db941bad43c392f4b2aa9becaaf7d2faaba01ffc
+    bb.js: ./dest/node/main.js
   languageName: node
-  linkType: hard
+  linkType: soft
 
 "@babel/code-frame@npm:^7.0.0, @babel/code-frame@npm:^7.10.4, @babel/code-frame@npm:^7.12.11, @babel/code-frame@npm:^7.16.0, @babel/code-frame@npm:^7.22.13, @babel/code-frame@npm:^7.23.5, @babel/code-frame@npm:^7.8.3":
   version: 7.23.5
@@ -4396,7 +4395,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "@noir-lang/backend_barretenberg@workspace:tooling/noir_js_backend_barretenberg"
   dependencies:
-    "@aztec/bb.js": 0.32.0
+    "@aztec/bb.js": "portal:../../../../barretenberg/ts"
     "@noir-lang/types": "workspace:*"
     "@types/node": ^20.6.2
     "@types/prettier": ^3