diff --git a/contracts/lendingpool/DefaultReserveInterestRateStrategy.sol b/contracts/lendingpool/DefaultReserveInterestRateStrategy.sol
index c8b9d9ec..224dd5d4 100644
--- a/contracts/lendingpool/DefaultReserveInterestRateStrategy.sol
+++ b/contracts/lendingpool/DefaultReserveInterestRateStrategy.sol
@@ -1,12 +1,11 @@
 // SPDX-License-Identifier: agpl-3.0
 pragma solidity ^0.6.8;
 
-import '../interfaces/IReserveInterestRateStrategy.sol';
-import '../libraries/WadRayMath.sol';
-import '../configuration/LendingPoolAddressesProvider.sol';
-import '../interfaces/ILendingRateOracle.sol';
-
-import '@openzeppelin/contracts/math/SafeMath.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
+import {IReserveInterestRateStrategy} from '../interfaces/IReserveInterestRateStrategy.sol';
+import {WadRayMath} from '../libraries/math/WadRayMath.sol';
+import {LendingPoolAddressesProvider} from '../configuration/LendingPoolAddressesProvider.sol';
+import {ILendingRateOracle} from '../interfaces/ILendingRateOracle.sol';
 
 /**
  * @title DefaultReserveInterestRateStrategy contract
diff --git a/contracts/lendingpool/LendingPool.sol b/contracts/lendingpool/LendingPool.sol
index 17f958ca..4e372c7f 100644
--- a/contracts/lendingpool/LendingPool.sol
+++ b/contracts/lendingpool/LendingPool.sol
@@ -2,29 +2,28 @@
 pragma solidity ^0.6.8;
 pragma experimental ABIEncoderV2;
 
-import '@openzeppelin/contracts/math/SafeMath.sol';
-import '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
-import '@openzeppelin/contracts/utils/Address.sol';
-import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-import '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
-
-import '../configuration/LendingPoolAddressesProvider.sol';
-import '../tokenization/AToken.sol';
-import '../libraries/WadRayMath.sol';
-import '../libraries/ReserveLogic.sol';
-import '../libraries/Helpers.sol';
-import '../libraries/GenericLogic.sol';
-import '../libraries/ValidationLogic.sol';
-import '../libraries/ReserveConfiguration.sol';
-import '../libraries/UserConfiguration.sol';
-import '../tokenization/interfaces/IStableDebtToken.sol';
-import '../tokenization/interfaces/IVariableDebtToken.sol';
-
-import '../flashloan/interfaces/IFlashLoanReceiver.sol';
-import './LendingPoolLiquidationManager.sol';
-import '../interfaces/IPriceOracleGetter.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
+import {ReentrancyGuard} from '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
+import {Address} from '@openzeppelin/contracts/utils/Address.sol';
+import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
+import {
+  VersionedInitializable
+} from '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
+import {LendingPoolAddressesProvider} from '../configuration/LendingPoolAddressesProvider.sol';
+import {AToken} from '../tokenization/AToken.sol';
+import {Helpers} from '../libraries/helpers/Helpers.sol';
+import {WadRayMath} from '../libraries/math/WadRayMath.sol';
+import {ReserveLogic} from '../libraries/logic/ReserveLogic.sol';
+import {GenericLogic} from '../libraries/logic/GenericLogic.sol';
+import {ValidationLogic} from '../libraries/logic/ValidationLogic.sol';
+import {ReserveConfiguration} from '../libraries/configuration/ReserveConfiguration.sol';
+import {UserConfiguration} from '../libraries/configuration/UserConfiguration.sol';
+import {IStableDebtToken} from '../tokenization/interfaces/IStableDebtToken.sol';
+import {IVariableDebtToken} from '../tokenization/interfaces/IVariableDebtToken.sol';
+import {IFlashLoanReceiver} from '../flashloan/interfaces/IFlashLoanReceiver.sol';
+import {LendingPoolLiquidationManager} from './LendingPoolLiquidationManager.sol';
+import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
 import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
-import '@nomiclabs/buidler/console.sol';
 
 /**
  * @title LendingPool contract
@@ -394,15 +393,6 @@ contract LendingPool is ReentrancyGuard, VersionedInitializable {
     );
   }
 
-  /**
-   * @notice repays a borrow on the specific reserve, for the specified amount (or for the whole amount, if uint256(-1) is specified).
-   * @dev the target user is defined by _onBehalfOf. If there is no repayment on behalf of another account,
-   * _onBehalfOf must be equal to msg.sender.
-   * @param _reserve the address of the reserve on which the user borrowed
-   * @param _amount the amount to repay, or uint256(-1) if the user wants to repay everything
-   * @param _onBehalfOf the address for which msg.sender is repaying.
-   **/
-
   struct RepayLocalVars {
     uint256 stableDebt;
     uint256 variableDebt;
@@ -411,6 +401,14 @@ contract LendingPool is ReentrancyGuard, VersionedInitializable {
     uint256 totalDebt;
   }
 
+  /**
+   * @notice repays a borrow on the specific reserve, for the specified amount (or for the whole amount, if uint256(-1) is specified).
+   * @dev the target user is defined by _onBehalfOf. If there is no repayment on behalf of another account,
+   * _onBehalfOf must be equal to msg.sender.
+   * @param _reserve the address of the reserve on which the user borrowed
+   * @param _amount the amount to repay, or uint256(-1) if the user wants to repay everything
+   * @param _onBehalfOf the address for which msg.sender is repaying.
+   **/
   function repay(
     address _reserve,
     uint256 _amount,
@@ -848,8 +846,7 @@ contract LendingPool is ReentrancyGuard, VersionedInitializable {
   }
 
   receive() external payable {
-    //only contracts can send ETH to the core
-    require(msg.sender.isContract(), '22');
+    revert();
   }
 
   /**
diff --git a/contracts/lendingpool/LendingPoolConfigurator.sol b/contracts/lendingpool/LendingPoolConfigurator.sol
index 2a7c0f7e..1846551b 100644
--- a/contracts/lendingpool/LendingPoolConfigurator.sol
+++ b/contracts/lendingpool/LendingPoolConfigurator.sol
@@ -2,15 +2,17 @@
 pragma solidity ^0.6.8;
 pragma experimental ABIEncoderV2;
 
-import '@openzeppelin/contracts/math/SafeMath.sol';
-
-import '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
-import '../libraries/ReserveConfiguration.sol';
-import '../configuration/LendingPoolAddressesProvider.sol';
-import '../libraries/openzeppelin-upgradeability/InitializableAdminUpgradeabilityProxy.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
+import {
+  VersionedInitializable
+} from '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
+import {
+  InitializableAdminUpgradeabilityProxy
+} from '../libraries/openzeppelin-upgradeability/InitializableAdminUpgradeabilityProxy.sol';
+import {ReserveConfiguration} from '../libraries/configuration/ReserveConfiguration.sol';
+import {LendingPoolAddressesProvider} from '../configuration/LendingPoolAddressesProvider.sol';
 import {LendingPool} from './LendingPool.sol';
 import {IERC20Detailed} from '../interfaces/IERC20Detailed.sol';
-import '@nomiclabs/buidler/console.sol';
 
 /**
  * @title LendingPoolConfigurator contract
diff --git a/contracts/lendingpool/LendingPoolLiquidationManager.sol b/contracts/lendingpool/LendingPoolLiquidationManager.sol
index cfc821d7..50a84213 100644
--- a/contracts/lendingpool/LendingPoolLiquidationManager.sol
+++ b/contracts/lendingpool/LendingPoolLiquidationManager.sol
@@ -1,26 +1,26 @@
 // SPDX-License-Identifier: agpl-3.0
 pragma solidity ^0.6.8;
 
-import '@openzeppelin/contracts/math/SafeMath.sol';
-import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-import '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
-import '@openzeppelin/contracts/utils/Address.sol';
-import '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
-
-import '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
-
-import '../configuration/LendingPoolAddressesProvider.sol';
-import '../tokenization/AToken.sol';
-import '../tokenization/interfaces/IStableDebtToken.sol';
-import '../tokenization/interfaces/IVariableDebtToken.sol';
-import '../libraries/WadRayMath.sol';
-import '../interfaces/IPriceOracleGetter.sol';
-import '../libraries/GenericLogic.sol';
-import '../libraries/Helpers.sol';
-import '../libraries/ReserveLogic.sol';
-import '../libraries/ReserveConfiguration.sol';
-import '../libraries/UserConfiguration.sol';
-import {PercentageMath} from '../libraries/PercentageMath.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
+import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
+import {ReentrancyGuard} from '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
+import {Address} from '@openzeppelin/contracts/utils/Address.sol';
+import {ReentrancyGuard} from '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
+import {
+  VersionedInitializable
+} from '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
+import {LendingPoolAddressesProvider} from '../configuration/LendingPoolAddressesProvider.sol';
+import {AToken} from '../tokenization/AToken.sol';
+import {IStableDebtToken} from '../tokenization/interfaces/IStableDebtToken.sol';
+import {IVariableDebtToken} from '../tokenization/interfaces/IVariableDebtToken.sol';
+import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
+import {GenericLogic} from '../libraries/logic/GenericLogic.sol';
+import {ReserveLogic} from '../libraries/logic/ReserveLogic.sol';
+import {ReserveConfiguration} from '../libraries/configuration/ReserveConfiguration.sol';
+import {UserConfiguration} from '../libraries/configuration/UserConfiguration.sol';
+import {Helpers} from '../libraries/helpers/Helpers.sol';
+import {WadRayMath} from '../libraries/math/WadRayMath.sol';
+import {PercentageMath} from '../libraries/math/PercentageMath.sol';
 import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
 
 /**
@@ -86,9 +86,6 @@ contract LendingPoolLiquidationManager is ReentrancyGuard, VersionedInitializabl
     uint256 actualAmountToLiquidate;
     uint256 liquidationRatio;
     uint256 maxAmountCollateralToLiquidate;
-    uint256 originationFee;
-    uint256 feeLiquidated;
-    uint256 liquidatedCollateralForFee;
     ReserveLogic.InterestRateMode borrowRateMode;
     uint256 userStableRate;
     uint256 maxCollateralToLiquidate;
diff --git a/contracts/libraries/ReserveConfiguration.sol b/contracts/libraries/configuration/ReserveConfiguration.sol
similarity index 97%
rename from contracts/libraries/ReserveConfiguration.sol
rename to contracts/libraries/configuration/ReserveConfiguration.sol
index b1ebb8e5..fe2cf490 100644
--- a/contracts/libraries/ReserveConfiguration.sol
+++ b/contracts/libraries/configuration/ReserveConfiguration.sol
@@ -3,11 +3,9 @@ pragma solidity ^0.6.8;
 
 import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-
-import {ReserveLogic} from './ReserveLogic.sol';
-import {WadRayMath} from './WadRayMath.sol';
-
-import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
+import {ReserveLogic} from '../logic/ReserveLogic.sol';
+import {WadRayMath} from '../math/WadRayMath.sol';
+import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
 
 /**
  * @title ReserveConfiguration library
diff --git a/contracts/libraries/UserConfiguration.sol b/contracts/libraries/configuration/UserConfiguration.sol
similarity index 96%
rename from contracts/libraries/UserConfiguration.sol
rename to contracts/libraries/configuration/UserConfiguration.sol
index b440ac12..9c41f332 100644
--- a/contracts/libraries/UserConfiguration.sol
+++ b/contracts/libraries/configuration/UserConfiguration.sol
@@ -3,9 +3,8 @@ pragma solidity ^0.6.8;
 
 import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-import {WadRayMath} from './WadRayMath.sol';
-import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
-
+import {WadRayMath} from '../math/WadRayMath.sol';
+import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
 /**
  * @title UserConfiguration library
  * @author Aave
diff --git a/contracts/libraries/Helpers.sol b/contracts/libraries/helpers/Helpers.sol
similarity index 79%
rename from contracts/libraries/Helpers.sol
rename to contracts/libraries/helpers/Helpers.sol
index de71cfa1..8f0b2db2 100644
--- a/contracts/libraries/Helpers.sol
+++ b/contracts/libraries/helpers/Helpers.sol
@@ -1,10 +1,8 @@
 // SPDX-License-Identifier: agpl-3.0
 pragma solidity ^0.6.8;
 
-import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-import '../tokenization/base/DebtTokenBase.sol';
-import './ReserveLogic.sol';
-
+import {DebtTokenBase} from '../../tokenization/base/DebtTokenBase.sol';
+import {ReserveLogic} from '../logic/ReserveLogic.sol';
 
 /**
  * @title Helpers library
@@ -12,7 +10,6 @@ import './ReserveLogic.sol';
  * @notice Implements calculation helpers.
  */
 library Helpers {
-
   /**
    * @dev fetches the user current stable and variable debt balances
    * @param _user the user
@@ -25,8 +22,8 @@ library Helpers {
     returns (uint256, uint256)
   {
     return (
-      IERC20(_reserve.stableDebtTokenAddress).balanceOf(_user),
-      IERC20(_reserve.variableDebtTokenAddress).balanceOf(_user)
+      DebtTokenBase(_reserve.stableDebtTokenAddress).balanceOf(_user),
+      DebtTokenBase(_reserve.variableDebtTokenAddress).balanceOf(_user)
     );
   }
 
diff --git a/contracts/libraries/GenericLogic.sol b/contracts/libraries/logic/GenericLogic.sol
similarity index 96%
rename from contracts/libraries/GenericLogic.sol
rename to contracts/libraries/logic/GenericLogic.sol
index 00392788..c8186ce1 100644
--- a/contracts/libraries/GenericLogic.sol
+++ b/contracts/libraries/logic/GenericLogic.sol
@@ -4,14 +4,12 @@ pragma experimental ABIEncoderV2;
 
 import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-
 import {ReserveLogic} from './ReserveLogic.sol';
-import {ReserveConfiguration} from './ReserveConfiguration.sol';
-import {UserConfiguration} from './UserConfiguration.sol';
-import {WadRayMath} from './WadRayMath.sol';
-import {PercentageMath} from './PercentageMath.sol';
-import '../interfaces/IPriceOracleGetter.sol';
-import '@nomiclabs/buidler/console.sol';
+import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
+import {UserConfiguration} from '../configuration/UserConfiguration.sol';
+import {WadRayMath} from '../math/WadRayMath.sol';
+import {PercentageMath} from '../math/PercentageMath.sol';
+import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
 
 /**
  * @title GenericLogic library
diff --git a/contracts/libraries/ReserveLogic.sol b/contracts/libraries/logic/ReserveLogic.sol
similarity index 72%
rename from contracts/libraries/ReserveLogic.sol
rename to contracts/libraries/logic/ReserveLogic.sol
index bdad33fb..48c36bc5 100644
--- a/contracts/libraries/ReserveLogic.sol
+++ b/contracts/libraries/logic/ReserveLogic.sol
@@ -3,18 +3,13 @@ pragma solidity ^0.6.8;
 
 import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-import {MathUtils} from './MathUtils.sol';
-import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
+import {MathUtils} from '../math/MathUtils.sol';
+import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
 import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
-import {IStableDebtToken} from '../tokenization/interfaces/IStableDebtToken.sol';
-import {ReserveConfiguration} from './ReserveConfiguration.sol';
-
-import '../configuration/LendingPoolAddressesProvider.sol';
-import '../interfaces/ILendingRateOracle.sol';
-import '../interfaces/IReserveInterestRateStrategy.sol';
-import '../tokenization/AToken.sol';
-import './WadRayMath.sol';
-import '@nomiclabs/buidler/console.sol';
+import {IStableDebtToken} from '../../tokenization/interfaces/IStableDebtToken.sol';
+import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
+import {IReserveInterestRateStrategy} from '../../interfaces/IReserveInterestRateStrategy.sol';
+import {WadRayMath} from '../math/WadRayMath.sol';
 
 /**
  * @title ReserveLogic library
@@ -25,16 +20,35 @@ library ReserveLogic {
   using SafeMath for uint256;
   using WadRayMath for uint256;
   using SafeERC20 for IERC20;
-  using Address for address;
+
+  /**
+   * @dev Emitted when the state of a reserve is updated
+   * @dev NOTE: This event replaces the Deprecated ReserveUpdated() event, which didn't emit the average stable borrow rate
+   * @param reserve the address of the reserve
+   * @param liquidityRate the new liquidity rate
+   * @param stableBorrowRate the new stable borrow rate
+   * @param averageStableBorrowRate the new average stable borrow rate
+   * @param variableBorrowRate the new variable borrow rate
+   * @param liquidityIndex the new liquidity index
+   * @param variableBorrowIndex the new variable borrow index
+   **/
+  event ReserveDataUpdated(
+    address indexed reserve,
+    uint256 liquidityRate,
+    uint256 stableBorrowRate,
+    uint256 averageStableBorrowRate,
+    uint256 variableBorrowRate,
+    uint256 liquidityIndex,
+    uint256 variableBorrowIndex
+  );
+
   using ReserveLogic for ReserveLogic.ReserveData;
   using ReserveConfiguration for ReserveConfiguration.Map;
 
   enum InterestRateMode {NONE, STABLE, VARIABLE}
 
+  // refer to the whitepaper, section 1.1 basic concepts for a formal description of these properties.
   struct ReserveData {
-    /**
-     * @dev refer to the whitepaper, section 1.1 basic concepts for a formal description of these properties.
-     **/
     //the liquidity index. Expressed in ray
     uint256 lastLiquidityCumulativeIndex;
     //the current supply rate. Expressed in ray
@@ -45,27 +59,21 @@ library ReserveLogic {
     uint256 currentStableBorrowRate;
     //variable borrow index. Expressed in ray
     uint256 lastVariableBorrowCumulativeIndex;
+    //stores the reserve configuration
     ReserveConfiguration.Map configuration;
-    /**
-     * @dev address of the aToken representing the asset
-     **/
     address payable aTokenAddress;
     address stableDebtTokenAddress;
     address variableDebtTokenAddress;
-    /**
-     * @dev address of the interest rate strategy contract
-     **/
     address interestRateStrategyAddress;
     uint40 lastUpdateTimestamp;
-    // isStableBorrowRateEnabled = true means users can borrow at a stable rate
-    bool isStableBorrowRateEnabled;
+    //the index of the reserve in the list of the active reserves
     uint8 index;
   }
 
   /**
    * @dev returns the ongoing normalized income for the reserve.
    * a value of 1e27 means there is no income. As time passes, the income is accrued.
-   * A value of 2*1e27 means that the income of the reserve is double the initial amount.
+   * A value of 2*1e27 means for each unit of assset two units of income have been accrued.
    * @param _reserve the reserve object
    * @return the normalized income. expressed in ray
    **/
@@ -114,10 +122,11 @@ library ReserveLogic {
    * @param _self the reserve object
    **/
   function updateCumulativeIndexesAndTimestamp(ReserveData storage _self) internal {
-    uint256 totalBorrows = getTotalBorrows(_self);
-
-    if (totalBorrows > 0) {
-      //only cumulating if there is any income being produced
+    //only cumulating if there is any income being produced
+    if (
+      IERC20(_self.variableDebtTokenAddress).totalSupply() > 0 ||
+      IERC20(_self.stableDebtTokenAddress).totalSupply() > 0
+    ) {
       uint256 cumulatedLiquidityInterest = MathUtils.calculateLinearInterest(
         _self.currentLiquidityRate,
         _self.lastUpdateTimestamp
@@ -190,34 +199,6 @@ library ReserveLogic {
     _self.interestRateStrategyAddress = _interestRateStrategyAddress;
   }
 
-  function getTotalBorrows(ReserveData storage _self) internal view returns (uint256) {
-    return
-      IERC20(_self.stableDebtTokenAddress).totalSupply().add(
-        IERC20(_self.variableDebtTokenAddress).totalSupply()
-      );
-  }
-
-  /**
-   * @dev Emitted when the state of a reserve is updated
-   * @dev NOTE: This event replaces the Deprecated ReserveUpdated() event, which didn't emit the average stable borrow rate
-   * @param reserve the address of the reserve
-   * @param liquidityRate the new liquidity rate
-   * @param stableBorrowRate the new stable borrow rate
-   * @param averageStableBorrowRate the new average stable borrow rate
-   * @param variableBorrowRate the new variable borrow rate
-   * @param liquidityIndex the new liquidity index
-   * @param variableBorrowIndex the new variable borrow index
-   **/
-  event ReserveDataUpdated(
-    address indexed reserve,
-    uint256 liquidityRate,
-    uint256 stableBorrowRate,
-    uint256 averageStableBorrowRate,
-    uint256 variableBorrowRate,
-    uint256 liquidityIndex,
-    uint256 variableBorrowIndex
-  );
-
   /**
    * @dev updates the state of the core as a result of a flashloan action
    * @param _reserve the address of the reserve in which the flashloan is happening
@@ -232,7 +213,9 @@ library ReserveLogic {
     //compounding the cumulated interest
     _reserve.updateCumulativeIndexesAndTimestamp();
 
-    uint256 totalLiquidityBefore = _availableLiquidityBefore.add(_reserve.getTotalBorrows());
+    uint256 totalLiquidityBefore = _availableLiquidityBefore
+      .add(IERC20(_reserve.variableDebtTokenAddress).totalSupply())
+      .add(IERC20(_reserve.stableDebtTokenAddress).totalSupply());
 
     //compounding the received fee into the reserve
     _reserve.cumulateToLiquidityIndex(totalLiquidityBefore, _income);
@@ -241,19 +224,6 @@ library ReserveLogic {
     updateInterestRates(_reserve, _reserveAddress, _income, 0);
   }
 
-  /**
-   * @dev gets the total liquidity in the reserve. The total liquidity is the balance of the core contract + total borrows
-   * @param _reserve the reserve address
-   * @return the total liquidity
-   **/
-  function getTotalLiquidity(ReserveData storage _reserve, address _reserveAddress)
-    public
-    view
-    returns (uint256)
-  {
-    return IERC20(_reserveAddress).balanceOf(address(this)).add(_reserve.getTotalBorrows());
-  }
-
   /**
    * @dev Updates the reserve current stable borrow rate Rf, the current variable borrow rate Rv and the current liquidity rate Rl.
    * Also updates the lastUpdateTimestamp value. Please refer to the whitepaper for further information.
@@ -298,56 +268,4 @@ library ReserveLogic {
       _reserve.lastVariableBorrowCumulativeIndex
     );
   }
-
-  /**
-   * @dev gets the reserve current variable borrow rate. Is the base variable borrow rate if the reserve is empty
-   * @param _reserve the reserve address
-   * @return the reserve current variable borrow rate
-   **/
-  function getReserveCurrentVariableBorrowRate(ReserveData storage _reserve)
-    external
-    view
-    returns (uint256)
-  {
-    if (_reserve.currentVariableBorrowRate == 0) {
-      return
-        IReserveInterestRateStrategy(_reserve.interestRateStrategyAddress)
-          .getBaseVariableBorrowRate();
-    }
-    return _reserve.currentVariableBorrowRate;
-  }
-
-  /**
-   * @dev gets the reserve current stable borrow rate. Is the market rate if the reserve is empty
-   * @param _reserve the reserve address
-   * @return the reserve current stable borrow rate
-   **/
-  function getReserveCurrentStableBorrowRate(ReserveData storage _reserve, uint256 _baseRate)
-    public
-    view
-    returns (uint256)
-  {
-    return _reserve.currentStableBorrowRate == 0 ? _baseRate : _reserve.currentStableBorrowRate;
-  }
-
-  /**
-   * @dev returns the utilization rate U of a specific reserve
-   * @param _reserve the reserve for which the information is needed
-   * @return the utilization rate in ray
-   **/
-  function getUtilizationRate(ReserveData storage _reserve, address _reserveAddress)
-    public
-    view
-    returns (uint256)
-  {
-    uint256 totalBorrows = _reserve.getTotalBorrows();
-
-    if (totalBorrows == 0) {
-      return 0;
-    }
-
-    uint256 availableLiquidity = IERC20(_reserveAddress).balanceOf(address(this));
-
-    return totalBorrows.rayDiv(availableLiquidity.add(totalBorrows));
-  }
 }
diff --git a/contracts/libraries/ValidationLogic.sol b/contracts/libraries/logic/ValidationLogic.sol
similarity index 96%
rename from contracts/libraries/ValidationLogic.sol
rename to contracts/libraries/logic/ValidationLogic.sol
index 50d2ae16..e6e58d72 100644
--- a/contracts/libraries/ValidationLogic.sol
+++ b/contracts/libraries/logic/ValidationLogic.sol
@@ -4,16 +4,14 @@ pragma experimental ABIEncoderV2;
 
 import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-
 import {ReserveLogic} from './ReserveLogic.sol';
 import {GenericLogic} from './GenericLogic.sol';
-import {WadRayMath} from './WadRayMath.sol';
-import {PercentageMath} from './PercentageMath.sol';
+import {WadRayMath} from '../math/WadRayMath.sol';
+import {PercentageMath} from '../math/PercentageMath.sol';
 import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
-import {ReserveConfiguration} from './ReserveConfiguration.sol';
-import {UserConfiguration} from './UserConfiguration.sol';
-import {IPriceOracleGetter} from '../interfaces/IPriceOracleGetter.sol';
-import '@nomiclabs/buidler/console.sol';
+import {ReserveConfiguration} from '../configuration/ReserveConfiguration.sol';
+import {UserConfiguration} from '../configuration/UserConfiguration.sol';
+import {IPriceOracleGetter} from '../../interfaces/IPriceOracleGetter.sol';
 
 /**
  * @title ReserveLogic library
@@ -35,12 +33,14 @@ library ValidationLogic {
    * @param _amount the amount to be deposited
    */
   function validateDeposit(ReserveLogic.ReserveData storage _reserve, uint256 _amount)
-    external
+    internal
     view
   {
     (bool isActive, bool isFreezed, , ) = _reserve.configuration.getFlags();
 
     require(_amount > 0, 'Amount must be greater than 0');
+    require(isActive, 'Action requires an active reserve');
+    require(!isFreezed, 'Action requires an unfreezed reserve');
   }
 
   /**
diff --git a/contracts/libraries/MathUtils.sol b/contracts/libraries/math/MathUtils.sol
similarity index 83%
rename from contracts/libraries/MathUtils.sol
rename to contracts/libraries/math/MathUtils.sol
index 1e26366d..e8d1dcbe 100644
--- a/contracts/libraries/MathUtils.sol
+++ b/contracts/libraries/math/MathUtils.sol
@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: agpl-3.0
 pragma solidity ^0.6.8;
 
-import '@openzeppelin/contracts/math/SafeMath.sol';
-import './WadRayMath.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
+import {WadRayMath} from './WadRayMath.sol';
 
 library MathUtils {
   using SafeMath for uint256;
@@ -34,7 +34,7 @@ library MathUtils {
    * @dev function to calculate the interest using a compounded interest rate formula.
    * To avoid expensive exponentiation, the calculation is performed using a binomial approximation:
    *
-   *  (1+x)^n = 1+n*x+[n/2*(n-1)]*x^2+[n/6*(n-1)*(n-2)*x^3...  
+   *  (1+x)^n = 1+n*x+[n/2*(n-1)]*x^2+[n/6*(n-1)*(n-2)*x^3...
    *
    * The approximation slightly underpays liquidity providers, with the advantage of great gas cost reductions.
    * The whitepaper contains reference to the approximation and a table showing the margin of error per different time periods.
@@ -48,30 +48,25 @@ library MathUtils {
     view
     returns (uint256)
   {
-
     //solium-disable-next-line
     uint256 exp = block.timestamp.sub(uint256(_lastUpdateTimestamp));
 
-    if(exp == 0){
+    if (exp == 0) {
       return WadRayMath.ray();
     }
 
-     uint256 expMinusOne = exp.sub(1);
+    uint256 expMinusOne = exp.sub(1);
 
-     uint256 expMinusTwo = exp > 2 ? exp.sub(2) : 0;
+    uint256 expMinusTwo = exp > 2 ? exp.sub(2) : 0;
 
     uint256 ratePerSecond = _rate.div(31536000);
-     
-     uint basePowerTwo = ratePerSecond.rayMul(ratePerSecond);
-     uint basePowerThree = basePowerTwo.rayMul(ratePerSecond);
 
+    uint256 basePowerTwo = ratePerSecond.rayMul(ratePerSecond);
+    uint256 basePowerThree = basePowerTwo.rayMul(ratePerSecond);
 
-    
     uint256 secondTerm = exp.mul(expMinusOne).mul(basePowerTwo).div(2);
     uint256 thirdTerm = exp.mul(expMinusOne).mul(expMinusTwo).mul(basePowerThree).div(6);
-    
 
     return WadRayMath.ray().add(ratePerSecond.mul(exp)).add(secondTerm).add(thirdTerm);
-
   }
 }
diff --git a/contracts/libraries/PercentageMath.sol b/contracts/libraries/math/PercentageMath.sol
similarity index 100%
rename from contracts/libraries/PercentageMath.sol
rename to contracts/libraries/math/PercentageMath.sol
diff --git a/contracts/libraries/WadRayMath.sol b/contracts/libraries/math/WadRayMath.sol
similarity index 97%
rename from contracts/libraries/WadRayMath.sol
rename to contracts/libraries/math/WadRayMath.sol
index 0dc29657..becf3d75 100644
--- a/contracts/libraries/WadRayMath.sol
+++ b/contracts/libraries/math/WadRayMath.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: agpl-3.0
 pragma solidity ^0.6.8;
 
-import '@openzeppelin/contracts/math/SafeMath.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 
 /**
  * @title WadRayMath library
@@ -112,5 +112,4 @@ library WadRayMath {
   function wadToRay(uint256 a) internal pure returns (uint256) {
     return a.mul(WAD_RAY_RATIO);
   }
-
 }
diff --git a/contracts/tokenization/AToken.sol b/contracts/tokenization/AToken.sol
index c30a07e9..0745e452 100644
--- a/contracts/tokenization/AToken.sol
+++ b/contracts/tokenization/AToken.sol
@@ -3,14 +3,12 @@ pragma solidity ^0.6.8;
 
 import {ERC20} from './ERC20.sol';
 import {LendingPool} from '../lendingpool/LendingPool.sol';
-import {WadRayMath} from '../libraries/WadRayMath.sol';
+import {WadRayMath} from '../libraries/math/WadRayMath.sol';
 import {SafeERC20} from '@openzeppelin/contracts/token/ERC20/SafeERC20.sol';
 import {
   VersionedInitializable
 } from '../libraries/openzeppelin-upgradeability/VersionedInitializable.sol';
 
-import '@nomiclabs/buidler/console.sol';
-
 /**
  * @title Aave ERC20 AToken
  *
diff --git a/contracts/tokenization/StableDebtToken.sol b/contracts/tokenization/StableDebtToken.sol
index 6fc51b6f..796d4215 100644
--- a/contracts/tokenization/StableDebtToken.sol
+++ b/contracts/tokenization/StableDebtToken.sol
@@ -5,8 +5,8 @@ import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
 import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
 import {Address} from '@openzeppelin/contracts/utils/Address.sol';
 import {DebtTokenBase} from './base/DebtTokenBase.sol';
-import {MathUtils} from '../libraries/MathUtils.sol';
-import {WadRayMath} from '../libraries/WadRayMath.sol';
+import {MathUtils} from '../libraries/math/MathUtils.sol';
+import {WadRayMath} from '../libraries/math/WadRayMath.sol';
 import {IStableDebtToken} from './interfaces/IStableDebtToken.sol';
 
 /**
diff --git a/contracts/tokenization/VariableDebtToken.sol b/contracts/tokenization/VariableDebtToken.sol
index 1e25ebfe..d75630b5 100644
--- a/contracts/tokenization/VariableDebtToken.sol
+++ b/contracts/tokenization/VariableDebtToken.sol
@@ -1,12 +1,11 @@
 pragma solidity ^0.6.0;
 
-import '@openzeppelin/contracts/GSN/Context.sol';
-import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
-import '@openzeppelin/contracts/math/SafeMath.sol';
-import '@openzeppelin/contracts/utils/Address.sol';
+import {Context} from '@openzeppelin/contracts/GSN/Context.sol';
+import {IERC20} from '@openzeppelin/contracts/token/ERC20/IERC20.sol';
+import {SafeMath} from '@openzeppelin/contracts/math/SafeMath.sol';
+import {Address} from '@openzeppelin/contracts/utils/Address.sol';
 import {DebtTokenBase} from './base/DebtTokenBase.sol';
-import {WadRayMath} from '../libraries/WadRayMath.sol';
-import '@nomiclabs/buidler/console.sol';
+import {WadRayMath} from '../libraries/math/WadRayMath.sol';
 import {IVariableDebtToken} from './interfaces/IVariableDebtToken.sol';
 
 /**
diff --git a/package-lock.json b/package-lock.json
index 0d69c5ed..0b5eff61 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -7524,6 +7524,7 @@
             "anymatch": "^2.0.0",
             "async-each": "^1.0.1",
             "braces": "^2.3.2",
+            "fsevents": "^1.2.7",
             "glob-parent": "^3.1.0",
             "inherits": "^2.0.3",
             "is-binary-path": "^1.0.0",
@@ -9990,6 +9991,17 @@
           "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8=",
           "dev": true
         },
+        "fsevents": {
+          "version": "1.2.13",
+          "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-1.2.13.tgz",
+          "integrity": "sha512-oWb1Z6mkHIskLzEJ/XWX0srkpkTQ7vaopMQkyaEIoq0fmtFVxOthb8cCxeT+p3ynTdkk/RZwbgG4brR5BeWECw==",
+          "dev": true,
+          "optional": true,
+          "requires": {
+            "bindings": "^1.5.0",
+            "nan": "^2.12.1"
+          }
+        },
         "function-bind": {
           "version": "1.1.1",
           "resolved": "https://registry.npmjs.org/function-bind/-/function-bind-1.1.1.tgz",
@@ -13213,6 +13225,7 @@
           "dev": true,
           "optional": true,
           "requires": {
+            "scrypt": "^6.0.2",
             "scryptsy": "^1.2.1"
           }
         },
@@ -18633,6 +18646,16 @@
         }
       }
     },
+    "scrypt": {
+      "version": "6.0.3",
+      "resolved": "https://registry.npmjs.org/scrypt/-/scrypt-6.0.3.tgz",
+      "integrity": "sha1-BOAUpWgrU/pQwtXM4WfXGcBthw0=",
+      "dev": true,
+      "optional": true,
+      "requires": {
+        "nan": "^2.0.8"
+      }
+    },
     "scrypt-js": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/scrypt-js/-/scrypt-js-3.0.1.tgz",