diff --git a/contracts/FundsRecovery.sol b/contracts/FundsRecovery.sol
index db803a9..9a74546 100644
--- a/contracts/FundsRecovery.sol
+++ b/contracts/FundsRecovery.sol
@@ -30,7 +30,7 @@ contract FundsRecovery is Ownable, ReentrancyGuard {
     /**
      * Possibility to recover funds in case they were sent to this address before smart contract deployment
      */
-    function claimEthers() public nonReentrant {
+    function claimNativeCoin() public nonReentrant {
         require(fundsDestination != address(0));
         fundsDestination.transfer(address(this).balance);
     }
diff --git a/contracts/HermesImplementation.sol b/contracts/HermesImplementation.sol
index 1cffa9b..c955310 100644
--- a/contracts/HermesImplementation.sol
+++ b/contracts/HermesImplementation.sol
@@ -110,11 +110,7 @@ contract HermesImplementation is FundsRecovery, Utils {
     event HermesStakeIncreased(uint256 newStake);
     event HermesPunishmentActivated(uint256 activationBlockTime);
     event HermesPunishmentDeactivated();
-
-    modifier onlyOperator() {
-        require(msg.sender == operator, "Hermes: only hermes operator can call this function");
-        _;
-    }
+    event HermesStakeReturned(address beneficiary);
 
     /*
       ------------------------------------------- SETUP -------------------------------------------
@@ -183,7 +179,7 @@ contract HermesImplementation is FundsRecovery, Utils {
         Channel storage _channel = channels[_channelId];
         require(_channel.settled > 0 || _channel.stake >= minStake || _ignoreStake, "Hermes: not enough stake");
 
-        // If there are not enought funds to rebalance we have to enable punishment mode.
+        // If there are not enough funds to rebalance we have to enable punishment mode.
         uint256 _availableBalance = availableBalance();
         if (_availableBalance < _channel.stake) {
             status = Status.Punishment;
@@ -293,7 +289,7 @@ contract HermesImplementation is FundsRecovery, Utils {
 
     // Anyone can increase channel's capacity by staking more into hermes
     function increaseStake(bytes32 _channelId, uint256 _amount) public {
-        require(getStatus() != Status.Closed, "hermes should be not closed");
+        require(getStatus() != Status.Closed, "Hermes: should be not closed");
         _increaseStake(_channelId, _amount, false);
     }
 
@@ -326,7 +322,7 @@ contract HermesImplementation is FundsRecovery, Utils {
         _channel.stake = _newStakeAmount;
         totalStake = totalStake - _amount;
 
-        // Pay transacor fee then withdraw the rest
+        // Pay transactor fee then withdraw the rest
         if (_transactorFee > 0) {
             token.transfer(msg.sender, _transactorFee);
         }
@@ -345,21 +341,19 @@ contract HermesImplementation is FundsRecovery, Utils {
     function resolveEmergency() public {
         require(getStatus() == Status.Punishment, "Hermes: should be in punishment status");
 
-        // 0.04% of total channels amount per time unit
-        uint256 _punishmentPerUnit = round(totalStake * PUNISHMENT_PERCENT, 100) / 100;
-
         // No punishment during first time unit
         uint256 _unit = getUnitTime();
         uint256 _timePassed = block.timestamp - punishment.activationBlockTime;
         uint256 _punishmentUnits = round(_timePassed, _unit) / _unit - 1;
 
-        uint256 _punishmentAmount = _punishmentUnits * _punishmentPerUnit;
+        // Using 0.04% of total channels amount per time unit
+        uint256 _punishmentAmount = _punishmentUnits * round(totalStake * PUNISHMENT_PERCENT, 100) / 100;
         punishment.amount = punishment.amount + _punishmentAmount;  // XXX alternativelly we could send tokens into BlackHole (0x0000000...)
 
         uint256 _shouldHave = minimalExpectedBalance() + maxStake;  // hermes should have funds for at least one maxStake settlement
         uint256 _currentBalance = token.balanceOf(address(this));
 
-        // If there are not enough available funds, they have to be topuped from msg.sender.
+        // If there are not enough available funds, they have to be topupped from msg.sender.
         if (_currentBalance < _shouldHave) {
             token.transferFrom(msg.sender, address(this), _shouldHave - _currentBalance);
         }
@@ -445,13 +439,13 @@ contract HermesImplementation is FundsRecovery, Utils {
         return _status != Status.Punishment && _status != Status.Closed;
     }
 
-    function pauseChannelOpening() public onlyOperator {
+    function pauseChannelOpening() public onlyOwner {
         require(getStatus() == Status.Active, "Hermes: have to be in active state");
         status = Status.Paused;
         emit ChannelOpeningPaused();
     }
 
-    function activateChannelOpening() public onlyOperator {
+    function activateChannelOpening() public onlyOwner {
         require(getStatus() == Status.Paused, "Hermes: have to be in paused state");
         status = Status.Active;
         emit ChannelOpeningActivated();
@@ -470,6 +464,8 @@ contract HermesImplementation is FundsRecovery, Utils {
 
         uint256 _amount = token.balanceOf(address(this)) - punishment.amount;
         token.transfer(_beneficiary, _amount);
+
+        emit HermesStakeReturned(_beneficiary);
     }
 
     /*
diff --git a/contracts/Migrations.sol b/contracts/Migrations.sol
index 57465ba..021f238 100644
--- a/contracts/Migrations.sol
+++ b/contracts/Migrations.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.7.0;
+pragma solidity 0.8.9;
 
 contract Migrations {
   address public owner;
diff --git a/contracts/Registry.sol b/contracts/Registry.sol
index 8b981ef..b39c421 100644
--- a/contracts/Registry.sol
+++ b/contracts/Registry.sol
@@ -17,7 +17,7 @@ contract Registry is FundsRecovery, Utils {
     uint256 public lastNonce;
     address payable public dex;     // Any uniswap v2 compatible DEX router address
     uint256 public minimalHermesStake;
-    Registry public parentRegistry; // If there is parent registry, we will check for
+    Registry public parentRegistry; // Contract could have parent registry if Registry SC was already upgraded
 
     struct Implementation {
         address channelImplAddress;
@@ -87,7 +87,7 @@ contract Registry is FundsRecovery, Utils {
 
         // Tokens amount to get from channel to cover tx fee and provider's stake
         uint256 _totalFee = _stakeAmount + _transactorFee;
-        require(_totalFee <= token.balanceOf(getChannelAddress(_identity, _hermesId)), "Registry: not enought funds in channel to cover fees");
+        require(_totalFee <= token.balanceOf(getChannelAddress(_identity, _hermesId)), "Registry: not enough funds in channel to cover fees");
 
         // Open consumer channel
         _openChannel(_identity, _hermesId, _beneficiary, _totalFee);
@@ -111,7 +111,7 @@ contract Registry is FundsRecovery, Utils {
         address _identity = keccak256(abi.encodePacked(getChainID(), address(this), _hermesId, _transactorFee)).recover(_signature);
         require(_identity != address(0), "Registry: wrong channel openinig signature");
 
-        require(_transactorFee <= token.balanceOf(getChannelAddress(_identity, _hermesId)), "Registry: not enought funds in channel to cover fees");
+        require(_transactorFee <= token.balanceOf(getChannelAddress(_identity, _hermesId)), "Registry: not enough funds in channel to cover fees");
 
         _openChannel(_identity, _hermesId, address(0), _transactorFee);
     }
diff --git a/contracts/interfaces/IERC20Token.sol b/contracts/interfaces/IERC20Token.sol
index 29ea799..046106e 100644
--- a/contracts/interfaces/IERC20Token.sol
+++ b/contracts/interfaces/IERC20Token.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.8.4;
+pragma solidity 0.8.9;
 
 import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 
diff --git a/contracts/interfaces/IHermesContract.sol b/contracts/interfaces/IHermesContract.sol
index 01662d6..3bef1d6 100644
--- a/contracts/interfaces/IHermesContract.sol
+++ b/contracts/interfaces/IHermesContract.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.7.6;
+pragma solidity 0.8.9;
 
 interface IHermesContract {
     enum Status { Active, Paused, Punishment, Closed }
diff --git a/contracts/interfaces/IUniswapV2Router.sol b/contracts/interfaces/IUniswapV2Router.sol
index 295eb68..531e012 100644
--- a/contracts/interfaces/IUniswapV2Router.sol
+++ b/contracts/interfaces/IUniswapV2Router.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.8.4;
+pragma solidity 0.8.9;
 
 interface IUniswapV2Router {
     function factory() external pure returns (address);
diff --git a/contracts/interfaces/IUpgradeAgent.sol b/contracts/interfaces/IUpgradeAgent.sol
index ca773be..636d5ee 100644
--- a/contracts/interfaces/IUpgradeAgent.sol
+++ b/contracts/interfaces/IUpgradeAgent.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-3.0
-pragma solidity >=0.8.4;
+pragma solidity 0.8.9;
 
 /**
  * Upgrade agent interface inspired by Lunyr.
diff --git a/test/fundsRecovery.js b/test/fundsRecovery.js
index 141dd62..450009a 100644
--- a/test/fundsRecovery.js
+++ b/test/fundsRecovery.js
@@ -54,7 +54,7 @@ contract('General tests for funds recovery', ([txMaker, owner, fundsDestination,
     it('anyone should successfully claim ethers', async () => {
         const initialBalance = await web3.eth.getBalance(fundsDestination)
 
-        await contract.claimEthers().should.be.fulfilled
+        await contract.claimNativeCoin().should.be.fulfilled
 
         const expectedBalance = Number(initialBalance) + topupAmount
         expect(await web3.eth.getBalance(fundsDestination)).to.be.equal(expectedBalance.toString())
@@ -112,7 +112,7 @@ contract('Registry funds recovery', ([_, txMaker, identity, account, fundsDestin
     it('should recover ethers sent to registry before its deployment', async () => {
         const initialBalance = new BN(await web3.eth.getBalance(fundsDestination))
         const amount = new BN(topupAmount.toString())
-        await registry.claimEthers().should.be.fulfilled
+        await registry.claimNativeCoin().should.be.fulfilled
         const expectedBalance = initialBalance.add(amount)
         expect(await web3.eth.getBalance(fundsDestination)).to.be.equal(expectedBalance.toString())
     })
@@ -161,7 +161,7 @@ contract('Channel implementation funds recovery', ([_, txMaker, identity, identi
     it('should recover ethers sent to identity implementation before its deployment', async () => {
         const initialBalance = new BN(await web3.eth.getBalance(fundsDestination))
         const amount = new BN(topupAmount.toString())
-        await channelImplementation.claimEthers().should.be.fulfilled
+        await channelImplementation.claimNativeCoin().should.be.fulfilled
 
         const expectedBalance = initialBalance.add(amount)
         expect(await web3.eth.getBalance(fundsDestination)).to.be.equal(expectedBalance.toString())
@@ -214,7 +214,7 @@ contract('Hermes funds recovery', ([_, txMaker, account, fundsDestination, ...ot
         const initialBalance = new BN(await web3.eth.getBalance(fundsDestination))
 
         topupAmount = new BN(topupAmount.toString())
-        await hermesImplementation.claimEthers().should.be.fulfilled
+        await hermesImplementation.claimNativeCoin().should.be.fulfilled
 
         const expectedBalance = topupAmount.add(new BN(initialBalance))
         expect(await web3.eth.getBalance(fundsDestination)).to.be.equal(expectedBalance.toString())
diff --git a/test/fundsRecoveryByCheque.js b/test/fundsRecoveryByCheque.js
index 356ae4b..df53099 100644
--- a/test/fundsRecoveryByCheque.js
+++ b/test/fundsRecoveryByCheque.js
@@ -80,7 +80,7 @@ contract('Full path (in channel using cheque) test for funds recovery', ([txMake
 
     it('should fail recovering funds when destination is not set', async () => {
         channel = await ChannelImplementation.at(expectedAddress)
-        await channel.claimEthers().should.be.rejected
+        await channel.claimNativeCoin().should.be.rejected
         expect(await channel.getFundsDestination()).to.be.equal(ZeroAddress)
     })
 
@@ -107,7 +107,7 @@ contract('Full path (in channel using cheque) test for funds recovery', ([txMake
     it('should recover ethers', async () => {
         const initialBalance = await web3.eth.getBalance(fundsDestination)
 
-        await channel.claimEthers({ from: otherAccounts[1] }).should.be.fulfilled
+        await channel.claimNativeCoin({ from: otherAccounts[1] }).should.be.fulfilled
 
         const expectedBalance = Number(initialBalance) + topupAmount
         expect(await web3.eth.getBalance(fundsDestination)).to.be.equal(expectedBalance.toString())
diff --git a/test/hermesPayAndSettle.js b/test/hermesPayAndSettle.js
index 34f0972..bde7934 100644
--- a/test/hermesPayAndSettle.js
+++ b/test/hermesPayAndSettle.js
@@ -53,7 +53,7 @@ contract('Pay and settle', ([txMaker, operatorAddress, ...otherAccounts]) => {
 
         // Topup some tokens into txMaker address so it could register hermes
         await topUpTokens(token, txMaker, OneToken)
-        await token.approve(registry.address, OneToken.add(OneToken))   // approve enought so it would enought for any case
+        await token.approve(registry.address, OneToken.add(OneToken))   // approve enough so it would enough for any case
     })
 
     it("should register and initialize hermes", async () => {
diff --git a/test/hermesStakeAndPunishment.js b/test/hermesStakeAndPunishment.js
index ab2220e..0a20ccc 100644
--- a/test/hermesStakeAndPunishment.js
+++ b/test/hermesStakeAndPunishment.js
@@ -44,10 +44,10 @@ contract('Hermes stake and punishment management', ([txMaker, operatorAddress, .
 
         // Topup some tokens into txMaker address so it could register hermes
         await topUpTokens(token, txMaker, OneToken)
-        await token.approve(registry.address, OneToken)   // approve a lot so it would enought for any case
+        await token.approve(registry.address, OneToken)   // approve a lot so it would enough for any case
     })
 
-    it('should reject hermes registration if he do not pay enought stake', async () => {
+    it('should reject hermes registration if he do not pay enough stake', async () => {
         const stateAmount = stake - 1
         await registry.registerHermes(hermesOperator.address, stateAmount, Zero, 25, OneToken, hermesURL).should.be.rejected
     })
@@ -172,7 +172,7 @@ contract('Hermes stake and punishment management', ([txMaker, operatorAddress, .
         const channelId = generateChannelId(provider.address, hermes.address)
         const initialChannelStake = (await hermes.channels(channelId)).stake
 
-        // txMaker should have enought tokens
+        // txMaker should have enough tokens
         await topUpTokens(token, txMaker, amountToStake)
         await token.approve(hermes.address, amountToStake)
 
@@ -221,7 +221,7 @@ contract('Hermes stake and punishment management', ([txMaker, operatorAddress, .
         expect(hermesStatus.toNumber()).to.be.equal(0)
         expect(await hermes.isHermesActive()).to.be.true
 
-        // Because emergency was resolved fast enought, punishment amount should be not increased
+        // Because emergency was resolved fast enough, punishment amount should be not increased
         const punishmentAmount = (await hermes.punishment()).amount
         punishmentAmount.should.be.bignumber.equal(initialPunishmentAmount)
     })
@@ -242,7 +242,7 @@ contract('Hermes stake and punishment management', ([txMaker, operatorAddress, .
         let signature = signIdentityRegistration(registry.address, hermes.address, channelStake, Zero, beneficiaries[1], newProvider)
         await registry.registerIdentity(hermes.address, channelStake, Zero, beneficiaries[1], signature)
 
-        // Ensure that hermes has enought funds
+        // Ensure that hermes has enough funds
         await topUpTokens(token, hermes.address, OneToken)
 
         // Should be able to settle promise
diff --git a/test/registry.js b/test/registry.js
index 40104b5..1a9f701 100644
--- a/test/registry.js
+++ b/test/registry.js
@@ -66,7 +66,7 @@ contract('Deterministic registry', ([txMaker, ...otherAccounts]) => {
     })
 
     it('should have hermes implementation deployed into deterministic address', async () => {
-        const expectedAddress = '0x98FC2aDD4692Dad03AD73AF4544da99db3033858'
+        const expectedAddress = '0xB6D6838664c7DB04Fe33F0E2EeD950Ac17a3dcbD'
         expect(await registry.getHermesImplementation()).to.be.equal(expectedAddress)
     })
 })