diff --git a/nucypher/blockchain/economics.py b/nucypher/blockchain/economics.py
index 34db922c1..5dd20cb8f 100644
--- a/nucypher/blockchain/economics.py
+++ b/nucypher/blockchain/economics.py
@@ -177,7 +177,8 @@ class SlashingEconomics:
     reward_coefficient = 2
 
     @property
-    def deployment_parameters(self):
+    def deployment_parameters(self) -> Tuple[int, ...]:
+        """Cast coefficient attributes to uint256 compatible type for solidity+EVM"""
 
         deployment_parameters = [
             self.algorithm_sha256,
@@ -187,4 +188,4 @@ class SlashingEconomics:
             self.reward_coefficient
         ]
 
-        return deployment_parameters
+        return tuple(map(int, deployment_parameters))
diff --git a/tests/blockchain/eth/contracts/integration/test_intercontract_integration.py b/tests/blockchain/eth/contracts/integration/test_intercontract_integration.py
index b6d675215..1a8ca37cb 100644
--- a/tests/blockchain/eth/contracts/integration/test_intercontract_integration.py
+++ b/tests/blockchain/eth/contracts/integration/test_intercontract_integration.py
@@ -18,21 +18,21 @@ along with nucypher.  If not, see <https://www.gnu.org/licenses/>.
 
 import os
 
-import coincurve
 import pytest
-from cryptography.hazmat.primitives.asymmetric import ec
+from cryptography.hazmat.backends.openssl import backend
+from cryptography.hazmat.primitives import hashes
 from eth_tester.exceptions import TransactionFailed
 from eth_utils import to_canonical_address
 from web3.contract import Contract
 
-from nucypher.blockchain.eth.token import NU
-from nucypher.policy.models import IndisputableEvidence
 from umbral import pre
 from umbral.curvebn import CurveBN
 from umbral.keys import UmbralPrivateKey
-from umbral.signing import Signer, Signature
-from cryptography.hazmat.backends.openssl import backend
-from cryptography.hazmat.primitives import hashes
+from umbral.signing import Signer
+
+from nucypher.blockchain.eth.token import NU
+from nucypher.crypto.utils import get_signature_recovery_value
+from nucypher.policy.models import IndisputableEvidence
 
 
 VALUE_FIELD = 0
@@ -46,12 +46,6 @@ policy_manager_secret = os.urandom(SECRET_LENGTH)
 user_escrow_secret = os.urandom(SECRET_LENGTH)
 adjudicator_secret = os.urandom(SECRET_LENGTH)
 
-ALGORITHM_SHA256 = 1
-BASE_PENALTY = 300
-PENALTY_HISTORY_COEFFICIENT = 10
-PERCENTAGE_PENALTY_COEFFICIENT = 2
-REWARD_COEFFICIENT = 2
-
 
 @pytest.fixture()
 def token(testerchain):
@@ -109,7 +103,7 @@ def policy_manager(testerchain, escrow):
 
 
 @pytest.fixture()
-def adjudicator(testerchain, escrow):
+def adjudicator(testerchain, escrow, slashing_economics):
     escrow, _ = escrow
     creator = testerchain.interface.w3.eth.accounts[0]
 
@@ -119,11 +113,8 @@ def adjudicator(testerchain, escrow):
     contract, _ = testerchain.interface.deploy_contract(
         'MiningAdjudicator',
         escrow.address,
-        ALGORITHM_SHA256,
-        BASE_PENALTY,
-        PENALTY_HISTORY_COEFFICIENT,
-        PERCENTAGE_PENALTY_COEFFICIENT,
-        REWARD_COEFFICIENT)
+        *slashing_economics.deployment_parameters)
+
     dispatcher, _ = testerchain.interface.deploy_contract('Dispatcher', contract.address, secret_hash)
 
     # Wrap dispatcher contract
@@ -140,26 +131,8 @@ def adjudicator(testerchain, escrow):
 
 # TODO: Obtain real re-encryption metadata. Maybe constructing a WorkOrder and obtaining a response.
 # TODO organize support functions
+# TODO: Repeated method in estimate_gas
 def generate_args_for_slashing(testerchain, miner):
-    def sign_data(data, umbral_privkey):
-        umbral_pubkey_bytes = umbral_privkey.get_pubkey().to_bytes(is_compressed=False)
-
-        # Prepare hash of the data
-        hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-        hash_ctx.update(data)
-        data_hash = hash_ctx.finalize()
-
-        # Sign data and calculate recoverable signature
-        cryptography_priv_key = umbral_privkey.to_cryptography_privkey()
-        signature_der_bytes = cryptography_priv_key.sign(data, ec.ECDSA(hashes.SHA256()))
-        signature = Signature.from_bytes(signature_der_bytes, der_encoded=True)
-        recoverable_signature = bytes(signature) + bytes([0])
-        pubkey_bytes = coincurve.PublicKey.from_signature_and_message(recoverable_signature, data_hash, hasher=None) \
-            .format(compressed=False)
-        if pubkey_bytes != umbral_pubkey_bytes:
-            recoverable_signature = bytes(signature) + bytes([1])
-        return recoverable_signature
-
     delegating_privkey = UmbralPrivateKey.gen_key()
     _symmetric_key, capsule = pre._encapsulate(delegating_privkey.get_pubkey())
     signing_privkey = UmbralPrivateKey.gen_key()
@@ -174,19 +147,34 @@ def generate_args_for_slashing(testerchain, miner):
                                  sign_delegating_key=False,
                                  sign_receiving_key=False)
     capsule.set_correctness_keys(delegating_privkey.get_pubkey(), pub_key_bob, signing_privkey.get_pubkey())
-    cfrag = pre.reencrypt(kfrags[0], capsule, metadata=os.urandom(34))
-    capsule_bytes = capsule.to_bytes()
-    # Corrupt proof
-    cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
-    cfrag_bytes = cfrag.to_bytes()
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    data_hash = hash_ctx.finalize()
-    requester_umbral_private_key = UmbralPrivateKey.gen_key()
-    requester_umbral_public_key_bytes = requester_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
+
     miner_umbral_private_key = UmbralPrivateKey.gen_key()
-    miner_umbral_public_key_bytes = miner_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)
+    ursula_pubkey = miner_umbral_private_key.get_pubkey()
+    ursula_pubkey_bytes = ursula_pubkey.to_bytes(is_compressed=False)[1:]
+    specification = bytes(capsule) + ursula_pubkey_bytes + bytes(20) + bytes(32)
+
+    ursulas_signer = Signer(miner_umbral_private_key)
+    bobs_signer = Signer(priv_key_bob)
+    task_signature = bytes(bobs_signer(specification))
+
+    metadata = bytes(ursulas_signer(task_signature))
+
+    cfrag = pre.reencrypt(kfrags[0], capsule, metadata=metadata)
+    cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
+
+    cfrag_signature = bytes(ursulas_signer(bytes(cfrag)))
+
+    bob_pubkey_bytes = pub_key_bob.to_bytes(is_compressed=False)[1:]
+
+    cfrag_signature_v = get_signature_recovery_value(message=bytes(cfrag),
+                                                     signature=cfrag_signature,
+                                                     public_key=ursula_pubkey)
+    task_signature_v = get_signature_recovery_value(message=task_signature,
+                                                    signature=metadata,
+                                                    public_key=ursula_pubkey)
+    recovery_values = cfrag_signature_v + task_signature_v
+
+    miner_umbral_public_key_bytes = miner_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)[1:]
     # Sign Umbral public key using eth-key
     hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
     hash_ctx.update(miner_umbral_public_key_bytes)
@@ -195,16 +183,19 @@ def generate_args_for_slashing(testerchain, miner):
     sig_key = testerchain.interface.provider.ethereum_tester.backend._key_lookup[address]
     signed_miner_umbral_public_key = bytes(sig_key.sign_msg_hash(miner_umbral_public_key_hash))
 
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
     evidence_data = evidence.precompute_values()
-    return data_hash, (capsule_bytes,
-                       capsule_signature_by_requester,
-                       capsule_signature_by_requester_and_miner,
-                       cfrag_bytes,
-                       cfrag_signature_by_miner,
-                       requester_umbral_public_key_bytes,
+
+    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
+    hash_ctx.update(bytes(capsule) + bytes(cfrag))
+    data_hash = hash_ctx.finalize()
+
+    return data_hash, (bytes(capsule),
+                       bytes(cfrag),
+                       cfrag_signature,
+                       task_signature,
+                       recovery_values,
+                       bob_pubkey_bytes,
                        miner_umbral_public_key_bytes,
                        signed_miner_umbral_public_key,
                        evidence_data)
@@ -272,7 +263,7 @@ def execute_multisig_transaction(testerchain, multisig, accounts, tx):
 
 
 @pytest.mark.slow
-def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escrow_proxy, multisig):
+def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escrow_proxy, multisig, slashing_economics):
     # Travel to the start of the next period to prevent problems with unexpected overflow first period
     testerchain.time_travel(hours=1)
 
@@ -780,19 +771,22 @@ def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escro
     total_lock = escrow.functions.lockedPerPeriod(period).call()
     alice1_balance = token.functions.balanceOf(alice1).call()
 
+    algorithm_sha256, base_penalty, *coefficients = slashing_economics.deployment_parameters
+    penalty_history_coefficient, percentage_penalty_coefficient, reward_coefficient = coefficients
+
     data_hash, slashing_args = generate_args_for_slashing(testerchain, ursula1)
     assert not adjudicator.functions.evaluatedCFrags(data_hash).call()
     tx = adjudicator.functions.evaluateCFrag(*slashing_args).transact({'from': alice1})
     testerchain.wait_for_receipt(tx)
     assert adjudicator.functions.evaluatedCFrags(data_hash).call()
-    assert tokens_amount - BASE_PENALTY == escrow.functions.minerInfo(ursula1).call()[VALUE_FIELD]
+    assert tokens_amount - base_penalty == escrow.functions.minerInfo(ursula1).call()[VALUE_FIELD]
     assert previous_lock == escrow.functions.getLockedTokensInPast(ursula1, 1).call()
     assert lock == escrow.functions.getLockedTokens(ursula1).call()
     assert next_lock == escrow.functions.getLockedTokens(ursula1, 1).call()
     assert total_previous_lock == escrow.functions.lockedPerPeriod(period - 1).call()
     assert total_lock == escrow.functions.lockedPerPeriod(period).call()
     assert 0 == escrow.functions.lockedPerPeriod(period + 1).call()
-    assert alice1_balance + BASE_PENALTY / REWARD_COEFFICIENT == token.functions.balanceOf(alice1).call()
+    assert alice1_balance + base_penalty / reward_coefficient == token.functions.balanceOf(alice1).call()
 
     # Slash part of the one sub stake
     tokens_amount = escrow.functions.minerInfo(ursula2).call()[VALUE_FIELD]
@@ -807,14 +801,14 @@ def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escro
     tx = adjudicator.functions.evaluateCFrag(*slashing_args).transact({'from': alice1})
     testerchain.wait_for_receipt(tx)
     assert adjudicator.functions.evaluatedCFrags(data_hash).call()
-    assert lock - BASE_PENALTY == escrow.functions.minerInfo(ursula2).call()[VALUE_FIELD]
+    assert lock - base_penalty == escrow.functions.minerInfo(ursula2).call()[VALUE_FIELD]
     assert previous_lock == escrow.functions.getLockedTokensInPast(ursula2, 1).call()
-    assert lock - BASE_PENALTY == escrow.functions.getLockedTokens(ursula2).call()
-    assert next_lock - BASE_PENALTY == escrow.functions.getLockedTokens(ursula2, 1).call()
+    assert lock - base_penalty == escrow.functions.getLockedTokens(ursula2).call()
+    assert next_lock - base_penalty == escrow.functions.getLockedTokens(ursula2, 1).call()
     assert total_previous_lock == escrow.functions.lockedPerPeriod(period - 1).call()
-    assert total_lock - BASE_PENALTY == escrow.functions.lockedPerPeriod(period).call()
+    assert total_lock - base_penalty == escrow.functions.lockedPerPeriod(period).call()
     assert 0 == escrow.functions.lockedPerPeriod(period + 1).call()
-    assert alice1_balance + BASE_PENALTY == token.functions.balanceOf(alice1).call()
+    assert alice1_balance + base_penalty == token.functions.balanceOf(alice1).call()
 
     # Upgrade the adjudicator
     # Deploy the same contract as the second version
@@ -822,11 +816,7 @@ def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escro
     adjudicator_v2, _ = testerchain.interface.deploy_contract(
         'MiningAdjudicator',
         escrow.address,
-        ALGORITHM_SHA256,
-        BASE_PENALTY,
-        PENALTY_HISTORY_COEFFICIENT,
-        PERCENTAGE_PENALTY_COEFFICIENT,
-        REWARD_COEFFICIENT)
+        *slashing_economics.deployment_parameters)
     adjudicator_secret2 = os.urandom(SECRET_LENGTH)
     adjudicator_secret2_hash = testerchain.interface.w3.keccak(adjudicator_secret2)
     # Ursula and Alice can't upgrade library, only owner can
@@ -900,7 +890,7 @@ def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escro
     tx = adjudicator.functions.evaluateCFrag(*slashing_args).transact({'from': alice2})
     testerchain.wait_for_receipt(tx)
     assert adjudicator.functions.evaluatedCFrags(data_hash).call()
-    penalty = (2 * BASE_PENALTY + 3 * PENALTY_HISTORY_COEFFICIENT)
+    penalty = (2 * base_penalty + 3 * penalty_history_coefficient)
     assert lock - penalty == escrow.functions.minerInfo(ursula1).call()[VALUE_FIELD]
     assert previous_lock == escrow.functions.getLockedTokensInPast(ursula1, 1).call()
     assert lock - penalty == escrow.functions.getLockedTokens(ursula1).call()
@@ -908,7 +898,7 @@ def test_all(testerchain, token, escrow, policy_manager, adjudicator, user_escro
     assert total_previous_lock == escrow.functions.lockedPerPeriod(period - 1).call()
     assert total_lock - penalty == escrow.functions.lockedPerPeriod(period).call()
     assert 0 == escrow.functions.lockedPerPeriod(period + 1).call()
-    assert alice2_balance + penalty / REWARD_COEFFICIENT == token.functions.balanceOf(alice2).call()
+    assert alice2_balance + penalty / reward_coefficient == token.functions.balanceOf(alice2).call()
 
     # Unlock and withdraw all tokens in MinersEscrow
     for index in range(9):
diff --git a/tests/blockchain/eth/contracts/main/mining_adjudicator/conftest.py b/tests/blockchain/eth/contracts/main/mining_adjudicator/conftest.py
index 9418c209d..09611e4df 100644
--- a/tests/blockchain/eth/contracts/main/mining_adjudicator/conftest.py
+++ b/tests/blockchain/eth/contracts/main/mining_adjudicator/conftest.py
@@ -34,11 +34,7 @@ def adjudicator_contract(testerchain, escrow, request, slashing_economics):
     contract, _ = testerchain.interface.deploy_contract(
         'MiningAdjudicator',
         escrow.address,
-        slashing_economics.algorithm_sha256,
-        slashing_economics.base_penalty,
-        slashing_economics.penalty_history_coefficient,
-        slashing_economics.percentage_penalty_coefficient,
-        slashing_economics.reward_coefficient)
+        *slashing_economics.deployment_parameters)
 
     if request.param:
         secret = os.urandom(DispatcherDeployer.DISPATCHER_SECRET_LENGTH)
diff --git a/tests/blockchain/eth/contracts/main/mining_adjudicator/test_mining_adjudicator.py b/tests/blockchain/eth/contracts/main/mining_adjudicator/test_mining_adjudicator.py
index 8babf1671..5fd277fc9 100644
--- a/tests/blockchain/eth/contracts/main/mining_adjudicator/test_mining_adjudicator.py
+++ b/tests/blockchain/eth/contracts/main/mining_adjudicator/test_mining_adjudicator.py
@@ -18,24 +18,21 @@ along with nucypher.  If not, see <https://www.gnu.org/licenses/>.
 
 import os
 
-import coincurve
 import pytest
 from cryptography.hazmat.backends.openssl import backend
 from cryptography.hazmat.primitives import hashes
-from cryptography.hazmat.primitives.asymmetric import ec
 from eth_tester.exceptions import TransactionFailed
-from eth_utils import to_canonical_address, to_checksum_address
+from eth_utils import to_canonical_address
 from typing import Tuple
 from web3.contract import Contract
 
 from umbral import pre
-from umbral.config import default_params
 from umbral.curvebn import CurveBN
 from umbral.keys import UmbralPrivateKey
 from umbral.point import Point
-from umbral.random_oracles import hash_to_curvebn, ExtendedKeccak
-from umbral.signing import Signature, Signer
+from umbral.signing import Signer
 
+from nucypher.crypto.utils import get_signature_recovery_value
 from nucypher.policy.models import IndisputableEvidence
 
 
@@ -45,33 +42,8 @@ secret = (123456).to_bytes(32, byteorder='big')
 secret2 = (654321).to_bytes(32, byteorder='big')
 
 
-def sign_data(data, umbral_privkey):
-    umbral_pubkey_bytes = umbral_privkey.get_pubkey().to_bytes(is_compressed=False)
-
-    # Prepare hash of the data
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(data)
-    data_hash = hash_ctx.finalize()
-
-    # Sign data and calculate recoverable signature
-    cryptography_priv_key = umbral_privkey.to_cryptography_privkey()
-    signature_der_bytes = cryptography_priv_key.sign(data, ec.ECDSA(hashes.SHA256()))
-    signature = Signature.from_bytes(signature_der_bytes, der_encoded=True)
-    recoverable_signature = make_recoverable_signature(data_hash, signature, umbral_pubkey_bytes)
-    return recoverable_signature
-
-
-def make_recoverable_signature(data_hash, signature, umbral_pubkey_bytes):
-    recoverable_signature = bytes(signature) + bytes([0])
-    pubkey_bytes = coincurve.PublicKey.from_signature_and_message(recoverable_signature, data_hash, hasher=None) \
-        .format(compressed=False)
-    if pubkey_bytes != umbral_pubkey_bytes:
-        recoverable_signature = bytes(signature) + bytes([1])
-    return recoverable_signature
-
-
 # TODO: Obtain real re-encryption metadata. Maybe constructing a WorkOrder and obtaining a response.
-def fragments(metadata):
+def mock_ursula_reencrypts(ursula_privkey, corrupt_cfrag: bool = False):
     delegating_privkey = UmbralPrivateKey.gen_key()
     _symmetric_key, capsule = pre._encapsulate(delegating_privkey.get_pubkey())
     signing_privkey = UmbralPrivateKey.gen_key()
@@ -86,8 +58,42 @@ def fragments(metadata):
                                  sign_delegating_key=False,
                                  sign_receiving_key=False)
     capsule.set_correctness_keys(delegating_privkey.get_pubkey(), pub_key_bob, signing_privkey.get_pubkey())
+
+    ursula_pubkey = ursula_privkey.get_pubkey()
+    ursula_pubkey_bytes = ursula_pubkey.to_bytes(is_compressed=False)[1:]
+    specification = bytes(capsule) + ursula_pubkey_bytes + bytes(20) + bytes(32)
+
+    ursulas_signer = Signer(ursula_privkey)
+    bobs_signer = Signer(priv_key_bob)
+    task_signature = bytes(bobs_signer(specification))
+
+    metadata = bytes(ursulas_signer(task_signature))
+
     cfrag = pre.reencrypt(kfrags[0], capsule, metadata=metadata)
-    return capsule, cfrag
+
+    if corrupt_cfrag:
+        cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
+
+    cfrag_signature = bytes(ursulas_signer(bytes(cfrag)))
+
+    bob_pubkey_bytes = pub_key_bob.to_bytes(is_compressed=False)[1:]
+
+    cfrag_signature_v = get_signature_recovery_value(message=bytes(cfrag),
+                                                     signature=cfrag_signature,
+                                                     public_key=ursula_pubkey)
+    task_signature_v = get_signature_recovery_value(message=task_signature,
+                                                    signature=metadata,
+                                                    public_key=ursula_pubkey)
+    recovery_values = cfrag_signature_v + task_signature_v
+
+    return capsule, cfrag, cfrag_signature, task_signature, recovery_values, bob_pubkey_bytes
+
+
+def evaluation_hash(capsule, cfrag):
+    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
+    hash_ctx.update(bytes(capsule) + bytes(cfrag))
+    data_hash = hash_ctx.finalize()
+    return data_hash
 
 
 @pytest.mark.slow
@@ -113,7 +119,7 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
 
     # Generate miner's Umbral key
     miner_umbral_private_key = UmbralPrivateKey.gen_key()
-    miner_umbral_public_key_bytes = miner_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)
+    miner_umbral_public_key_bytes = miner_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)[1:]
 
     # Sign Umbral public key using eth-key
     hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
@@ -124,43 +130,28 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     sig_key = provider.ethereum_tester.backend._key_lookup[address]
     signed_miner_umbral_public_key = bytes(sig_key.sign_msg_hash(miner_umbral_public_key_hash))
 
-    # Prepare hash of the data
-    metadata = os.urandom(33)
-    capsule, cfrag = fragments(metadata)
-
+    # Prepare evaluation data
+    capsule, cfrag, *other_stuff = mock_ursula_reencrypts(miner_umbral_private_key)
+    cfrag_signature, task_signature, recovery_values, bob_pubkey_bytes = other_stuff
     assert cfrag.verify_correctness(capsule)
 
-    capsule_bytes = capsule.to_bytes()
-    cfrag_bytes = cfrag.to_bytes()
-
-    # Bob prepares supporting Evidence
+    # Investigator prepares supporting Evidence
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
 
     evidence_data = evidence.precompute_values()
     assert len(evidence_data) == 20 * 32 + 32 + 20 + 1
 
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    data_hash = hash_ctx.finalize()
+    data_hash = evaluation_hash(capsule, cfrag)
     # This capsule and cFrag are not yet evaluated
     assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
 
-    # Generate requester's Umbral key
-    requester_umbral_private_key = UmbralPrivateKey.gen_key()
-    requester_umbral_public_key_bytes = requester_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)
-
-    # Sign capsule and cFrag
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
-
     # Challenge using good data
-    args = (capsule_bytes,
-            capsule_signature_by_requester,
-            capsule_signature_by_requester_and_miner,
-            cfrag_bytes,
-            cfrag_signature_by_miner,
-            requester_umbral_public_key_bytes,
+    args = (bytes(capsule),
+            bytes(cfrag),
+            cfrag_signature,
+            task_signature,
+            recovery_values,
+            bob_pubkey_bytes,
             miner_umbral_public_key_bytes,
             signed_miner_umbral_public_key,
             evidence_data)
@@ -183,39 +174,36 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     assert investigator == event_args['investigator']
     assert event_args['correctness']
 
+    ###############################
     # Test: Don't evaluate miner with data that already was checked
+    ###############################
+    # TODO: be more specific on the expected exception
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*args).transact()
         testerchain.wait_for_receipt(tx)
 
+    ###############################
     # Test: Ursula produces incorrect proof:
-    metadata = os.urandom(34)
-    capsule, cfrag = fragments(metadata)
-    capsule_bytes = capsule.to_bytes()
-    # Corrupt proof
-    cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
-    cfrag_bytes = cfrag.to_bytes()
+    ###############################
+    capsule, cfrag, *other_stuff = mock_ursula_reencrypts(miner_umbral_private_key, corrupt_cfrag=True)
+    cfrag_signature, task_signature, recovery_values, bob_pubkey_bytes = other_stuff
     assert not cfrag.verify_correctness(capsule)
 
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    data_hash = hash_ctx.finalize()
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
     evidence_data = evidence.precompute_values()
-    args = (capsule_bytes,
-            capsule_signature_by_requester,
-            capsule_signature_by_requester_and_miner,
-            cfrag_bytes,
-            cfrag_signature_by_miner,
-            requester_umbral_public_key_bytes,
+    args = (bytes(capsule),
+            bytes(cfrag),
+            cfrag_signature,
+            task_signature,
+            recovery_values,
+            bob_pubkey_bytes,
             miner_umbral_public_key_bytes,
             signed_miner_umbral_public_key,
             evidence_data)
 
+    data_hash = evaluation_hash(capsule, cfrag)
     assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
+
     tx = adjudicator_contract.functions.evaluateCFrag(*args).transact({'from': investigator})
     testerchain.wait_for_receipt(tx)
     number_of_evaluations += 1
@@ -243,18 +231,10 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     # Test: Bob produces wrong precomputed data
     ###############################
 
-    metadata = os.urandom(34)
-    capsule, cfrag = fragments(metadata)
-    capsule_bytes = capsule.to_bytes()
-    cfrag_bytes = cfrag.to_bytes()
+    capsule, cfrag, *other_stuff = mock_ursula_reencrypts(miner_umbral_private_key)
+    cfrag_signature, task_signature, recovery_values, bob_pubkey_bytes = other_stuff
     assert cfrag.verify_correctness(capsule)
 
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    data_hash = hash_ctx.finalize()
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
     evidence_data = evidence.precompute_values()
 
@@ -265,16 +245,17 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     evidence_data[32:32+64] = random_point_bytes
     evidence_data = bytes(evidence_data)
 
-    args = (capsule_bytes,
-            capsule_signature_by_requester,
-            capsule_signature_by_requester_and_miner,
-            cfrag_bytes,
-            cfrag_signature_by_miner,
-            requester_umbral_public_key_bytes,
+    args = (bytes(capsule),
+            bytes(cfrag),
+            cfrag_signature,
+            task_signature,
+            recovery_values,
+            bob_pubkey_bytes,
             miner_umbral_public_key_bytes,
             signed_miner_umbral_public_key,
             evidence_data)
 
+    data_hash = evaluation_hash(capsule, cfrag)
     assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
 
     # Evaluation must fail since Bob precomputed wrong values
@@ -292,34 +273,27 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     # Test: Second violation. Penalty is increased
     ###############################
 
-    # Prepare hash of the data
-    metadata = os.urandom(34)
-    capsule, cfrag = fragments(metadata)
-    capsule_bytes = capsule.to_bytes()
-    # Corrupt proof
-    cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
-    cfrag_bytes = cfrag.to_bytes()
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    data_hash = hash_ctx.finalize()
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
+    capsule, cfrag, *other_stuff = mock_ursula_reencrypts(miner_umbral_private_key, corrupt_cfrag=True)
+    cfrag_signature, task_signature, recovery_values, bob_pubkey_bytes = other_stuff
+
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
     evidence_data = evidence.precompute_values()
-    args = [capsule_bytes,
-            capsule_signature_by_requester,
-            capsule_signature_by_requester_and_miner,
-            cfrag_bytes,
-            cfrag_signature_by_miner,
-            requester_umbral_public_key_bytes,
+    args = (bytes(capsule),
+            bytes(cfrag),
+            cfrag_signature,
+            task_signature,
+            recovery_values,
+            bob_pubkey_bytes,
             miner_umbral_public_key_bytes,
             signed_miner_umbral_public_key,
-            evidence_data]
+            evidence_data)
+
+    data_hash = evaluation_hash(capsule, cfrag)
     assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
 
     worker_stake = escrow.functions.minerInfo(miner).call()[0]
     investigator_balance = escrow.functions.rewardInfo(investigator).call()
+
     assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
     tx = adjudicator_contract.functions.evaluateCFrag(*args).transact({'from': investigator})
     testerchain.wait_for_receipt(tx)
@@ -350,33 +324,27 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     # Test: Third violation. Penalty reaches the maximum allowed
     ###############################
 
-    # Prepare corrupted data again
-    capsule, cfrag = fragments(metadata)
-    capsule_bytes = capsule.to_bytes()
-    # Corrupt proof
-    cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
-    cfrag_bytes = cfrag.to_bytes()
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    data_hash = hash_ctx.finalize()
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
+    capsule, cfrag, *other_stuff = mock_ursula_reencrypts(miner_umbral_private_key, corrupt_cfrag=True)
+    cfrag_signature, task_signature, recovery_values, bob_pubkey_bytes = other_stuff
+
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
     evidence_data = evidence.precompute_values()
-    args = [capsule_bytes,
-            capsule_signature_by_requester,
-            capsule_signature_by_requester_and_miner,
-            cfrag_bytes,
-            cfrag_signature_by_miner,
-            requester_umbral_public_key_bytes,
+    args = (bytes(capsule),
+            bytes(cfrag),
+            cfrag_signature,
+            task_signature,
+            recovery_values,
+            bob_pubkey_bytes,
             miner_umbral_public_key_bytes,
             signed_miner_umbral_public_key,
-            evidence_data]
+            evidence_data)
+
+    data_hash = evaluation_hash(capsule, cfrag)
+    assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
 
     worker_stake = escrow.functions.minerInfo(miner).call()[0]
     investigator_balance = escrow.functions.rewardInfo(investigator).call()
-    assert not adjudicator_contract.functions.evaluatedCFrags(data_hash).call()
+
     tx = adjudicator_contract.functions.evaluateCFrag(*args).transact({'from': investigator})
     testerchain.wait_for_receipt(tx)
     number_of_evaluations += 1
@@ -406,47 +374,40 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     ##############
 
     # Can't evaluate miner using broken signatures
-    wrong_args = args[:]
-    wrong_args[1] = capsule_signature_by_requester[1:]
+    wrong_args = list(args)
+    wrong_args[2] = cfrag_signature[1:]
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
         testerchain.wait_for_receipt(tx)
-    wrong_args = args[:]
-    wrong_args[2] = capsule_signature_by_requester_and_miner[1:]
+
+    wrong_args = list(args)
+    wrong_args[3] = task_signature[1:]
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
         testerchain.wait_for_receipt(tx)
-    wrong_args = args[:]
-    wrong_args[4] = cfrag_signature_by_miner[1:]
-    with pytest.raises((TransactionFailed, ValueError)):
-        tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
-        testerchain.wait_for_receipt(tx)
-    wrong_args = args[:]
+
+    wrong_args = list(args)
     wrong_args[7] = signed_miner_umbral_public_key[1:]
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
         testerchain.wait_for_receipt(tx)
 
     # Can't evaluate miner using wrong keys
-    wrong_args = args[:]
-    wrong_args[5] = UmbralPrivateKey.gen_key().get_pubkey().to_bytes(is_compressed=False)
+    wrong_args = list(args)
+    wrong_args[5] = UmbralPrivateKey.gen_key().get_pubkey().to_bytes(is_compressed=False)[1:]
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
         testerchain.wait_for_receipt(tx)
-    wrong_args = args[:]
-    wrong_args[6] = UmbralPrivateKey.gen_key().get_pubkey().to_bytes(is_compressed=False)
+
+    wrong_args = list(args)
+    wrong_args[6] = UmbralPrivateKey.gen_key().get_pubkey().to_bytes(is_compressed=False)[1:]
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
         testerchain.wait_for_receipt(tx)
 
     # Can't use signature for another data
-    wrong_args = args[:]
-    wrong_args[0] = bytes(args[0][0] + 1) + args[0][1:]
-    with pytest.raises((TransactionFailed, ValueError)):
-        tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
-        testerchain.wait_for_receipt(tx)
-    wrong_args = args[:]
-    wrong_args[3] = bytes(args[3][0] + 1) + args[3][1:]
+    wrong_args = list(args)
+    wrong_args[1] = os.urandom(len(bytes(cfrag)))
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
         testerchain.wait_for_receipt(tx)
@@ -455,7 +416,8 @@ def test_evaluate_cfrag(testerchain, escrow, adjudicator_contract, slashing_econ
     address = to_canonical_address(wrong_miner)
     sig_key = provider.ethereum_tester.backend._key_lookup[address]
     signed_wrong_miner_umbral_public_key = bytes(sig_key.sign_msg_hash(miner_umbral_public_key_hash))
-    wrong_args = args[:]
+
+    wrong_args = list(args)
     wrong_args[7] = signed_wrong_miner_umbral_public_key
     with pytest.raises((TransactionFailed, ValueError)):
         tx = adjudicator_contract.functions.evaluateCFrag(*wrong_args).transact()
diff --git a/tests/metrics/estimate_gas.py b/tests/metrics/estimate_gas.py
index bc73d6fa8..61930db2d 100755
--- a/tests/metrics/estimate_gas.py
+++ b/tests/metrics/estimate_gas.py
@@ -18,34 +18,29 @@ You should have received a copy of the GNU Affero General Public License
 along with nucypher.  If not, see <https://www.gnu.org/licenses/>.
 """
 
-import coincurve
+import io
 import json
 import os
-
-from cryptography.hazmat.primitives.asymmetric import ec
-from eth_utils import to_canonical_address
-
-from nucypher.blockchain.economics import TokenEconomics
-from nucypher.policy.models import IndisputableEvidence, Policy
-from umbral import pre
-from umbral.curvebn import CurveBN
-from umbral.keys import UmbralPrivateKey
-from umbral.signing import Signer, Signature
-
+import re
 import time
 from os.path import abspath, dirname
 
-import io
-import re
-
+from eth_utils import to_canonical_address
 from cryptography.hazmat.backends.openssl import backend
 from cryptography.hazmat.primitives import hashes
 from twisted.logger import globalLogPublisher, Logger, jsonFileLogObserver, ILogObserver
 from zope.interface import provider
 
-from nucypher.blockchain.eth.agents import NucypherTokenAgent, MinerAgent, PolicyAgent, MiningAdjudicatorAgent
-from nucypher.utilities.sandbox.blockchain import TesterBlockchain
+from umbral import pre
+from umbral.curvebn import CurveBN
+from umbral.keys import UmbralPrivateKey
+from umbral.signing import Signer
 
+from nucypher.blockchain.economics import TokenEconomics
+from nucypher.blockchain.eth.agents import NucypherTokenAgent, MinerAgent, PolicyAgent, MiningAdjudicatorAgent
+from nucypher.crypto.utils import get_signature_recovery_value
+from nucypher.policy.models import IndisputableEvidence, Policy
+from nucypher.utilities.sandbox.blockchain import TesterBlockchain
 
 ALGORITHM_SHA256 = 1
 TOKEN_ECONOMICS = TokenEconomics()
@@ -121,26 +116,8 @@ class AnalyzeGas:
 
 
 # TODO organize support functions
+# TODO: Repeated method in test_intercontract_integration
 def generate_args_for_slashing(testerchain, miner, corrupt: bool = True):
-    def sign_data(data, umbral_privkey):
-        umbral_pubkey_bytes = umbral_privkey.get_pubkey().to_bytes(is_compressed=False)
-
-        # Prepare hash of the data
-        hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-        hash_ctx.update(data)
-        data_hash = hash_ctx.finalize()
-
-        # Sign data and calculate recoverable signature
-        cryptography_priv_key = umbral_privkey.to_cryptography_privkey()
-        signature_der_bytes = cryptography_priv_key.sign(data, ec.ECDSA(hashes.SHA256()))
-        signature = Signature.from_bytes(signature_der_bytes, der_encoded=True)
-        recoverable_signature = bytes(signature) + bytes([0])
-        pubkey_bytes = coincurve.PublicKey.from_signature_and_message(recoverable_signature, data_hash, hasher=None) \
-            .format(compressed=False)
-        if pubkey_bytes != umbral_pubkey_bytes:
-            recoverable_signature = bytes(signature) + bytes([1])
-        return recoverable_signature
-
     delegating_privkey = UmbralPrivateKey.gen_key()
     _symmetric_key, capsule = pre._encapsulate(delegating_privkey.get_pubkey())
     signing_privkey = UmbralPrivateKey.gen_key()
@@ -155,18 +132,35 @@ def generate_args_for_slashing(testerchain, miner, corrupt: bool = True):
                                  sign_delegating_key=False,
                                  sign_receiving_key=False)
     capsule.set_correctness_keys(delegating_privkey.get_pubkey(), pub_key_bob, signing_privkey.get_pubkey())
-    cfrag = pre.reencrypt(kfrags[0], capsule, metadata=os.urandom(34))
-    capsule_bytes = capsule.to_bytes()
+
+    miner_umbral_private_key = UmbralPrivateKey.gen_key()
+    ursula_pubkey = miner_umbral_private_key.get_pubkey()
+    ursula_pubkey_bytes = ursula_pubkey.to_bytes(is_compressed=False)[1:]
+    specification = bytes(capsule) + ursula_pubkey_bytes + bytes(20) + bytes(32)
+
+    ursulas_signer = Signer(miner_umbral_private_key)
+    bobs_signer = Signer(priv_key_bob)
+    task_signature = bytes(bobs_signer(specification))
+
+    metadata = bytes(ursulas_signer(task_signature))
+
+    cfrag = pre.reencrypt(kfrags[0], capsule, metadata=metadata)
     if corrupt:
         cfrag.proof.bn_sig = CurveBN.gen_rand(capsule.params.curve)
-    cfrag_bytes = cfrag.to_bytes()
-    hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
-    hash_ctx.update(capsule_bytes + cfrag_bytes)
-    requester_umbral_private_key = UmbralPrivateKey.gen_key()
-    requester_umbral_public_key_bytes = requester_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)
-    capsule_signature_by_requester = sign_data(capsule_bytes, requester_umbral_private_key)
-    miner_umbral_private_key = UmbralPrivateKey.gen_key()
-    miner_umbral_public_key_bytes = miner_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)
+
+    cfrag_signature = bytes(ursulas_signer(bytes(cfrag)))
+
+    bob_pubkey_bytes = pub_key_bob.to_bytes(is_compressed=False)[1:]
+
+    cfrag_signature_v = get_signature_recovery_value(message=bytes(cfrag),
+                                                     signature=cfrag_signature,
+                                                     public_key=ursula_pubkey)
+    task_signature_v = get_signature_recovery_value(message=task_signature,
+                                                    signature=metadata,
+                                                    public_key=ursula_pubkey)
+    recovery_values = cfrag_signature_v + task_signature_v
+
+    miner_umbral_public_key_bytes = miner_umbral_private_key.get_pubkey().to_bytes(is_compressed=False)[1:]
     # Sign Umbral public key using eth-key
     hash_ctx = hashes.Hash(hashes.SHA256(), backend=backend)
     hash_ctx.update(miner_umbral_public_key_bytes)
@@ -175,16 +169,15 @@ def generate_args_for_slashing(testerchain, miner, corrupt: bool = True):
     sig_key = testerchain.interface.provider.ethereum_tester.backend._key_lookup[address]
     signed_miner_umbral_public_key = bytes(sig_key.sign_msg_hash(miner_umbral_public_key_hash))
 
-    capsule_signature_by_requester_and_miner = sign_data(capsule_signature_by_requester, miner_umbral_private_key)
-    cfrag_signature_by_miner = sign_data(cfrag_bytes, miner_umbral_private_key)
     evidence = IndisputableEvidence(capsule, cfrag, ursula=None)
     evidence_data = evidence.precompute_values()
-    return (capsule_bytes,
-            capsule_signature_by_requester,
-            capsule_signature_by_requester_and_miner,
-            cfrag_bytes,
-            cfrag_signature_by_miner,
-            requester_umbral_public_key_bytes,
+
+    return (bytes(capsule),
+            bytes(cfrag),
+            cfrag_signature,
+            task_signature,
+            recovery_values,
+            bob_pubkey_bytes,
             miner_umbral_public_key_bytes,
             signed_miner_umbral_public_key,
             evidence_data)