Bump to version 2.0.2

* Remove variables initialization on declaration for SplitPayment contracts

.github/PULL_REQUEST_TEMPLATE.md

@@ -14,4 +14,4 @@ Fixes #
 - [ ] 📘 I've reviewed the [OpenZeppelin Contributor Guidelines](../blob/master/CONTRIBUTING.md)
 - [ ] ✅ I've added tests where applicable to test my new functionality.
 - [ ] 📖 I've made sure that my contracts are well-documented.
-- [ ] 🎨 I've run the JS/Solidity linters and fixed any issues (`npm run lint:all:fix`).
+- [ ] 🎨 I've run the JS/Solidity linters and fixed any issues (`npm run lint:fix`).

.gitignore

@@ -37,3 +37,5 @@ build/
 
 # truffle
 .node-xmlhttprequest-*
+
+.zos.session

.soliumrc.json

@@ -6,7 +6,7 @@
     "indentation": ["error", 2],
     "lbrace": "off",
     "linebreak-style": ["error", "unix"],
-    "max-len": ["error", 79],
+    "max-len": ["error", 120],
     "no-constant": ["error"],
     "no-empty-blocks": "off",
     "quotes": ["error", "double"],

.travis.yml

@@ -18,6 +18,11 @@ jobs:
     - env: SOLIDITY_COVERAGE=true
     - env: SOLC_NIGHTLY=true
   include:
+    - stage: install
+      script: true
+      install:
+        - npm install
+        - npx npm-install-peers
     # Run the unit test suite three times in parallel.
     # The first one gets results faster and is the only one required to pass.
     # The second one generates the coverage report.
@@ -25,18 +30,22 @@ jobs:
     # upcoming solidity release.
     - stage: tests
       name: "unit tests"
+      install: npx npm-install-peers
       script: npm run test
     - stage: tests
       name: "unit tests with coverage"
+      install: npx npm-install-peers
       script: npm run test
       env: SOLIDITY_COVERAGE=true
     - stage: tests
       name: "unit tests with solc nightly"
+      install: npx npm-install-peers
       script: npm run test
       env: SOLC_NIGHTLY=true
     # solidity and javascript style tests.
     - stage: tests
       name: "static tests"
+      install: npx npm-install-peers
       script: npm run lint
     - stage: update docs
       if: tag =~ ^v[0-9]+\.[0-9]+\.[0-9]+$

README.md

@@ -1,54 +1,30 @@
 # <img src="logo.png" alt="OpenZeppelin" width="400px">
 
-[![NPM Package](https://img.shields.io/npm/v/openzeppelin-solidity.svg?style=flat-square)](https://www.npmjs.org/package/openzeppelin-solidity)
-[![Build Status](https://img.shields.io/travis/OpenZeppelin/openzeppelin-solidity.svg?branch=master&style=flat-square)](https://travis-ci.org/OpenZeppelin/openzeppelin-solidity)
-[![Coverage Status](https://img.shields.io/coveralls/github/OpenZeppelin/openzeppelin-solidity/master.svg?style=flat-square)](https://coveralls.io/github/OpenZeppelin/openzeppelin-solidity?branch=master)
+# OpenZeppelin EVM Package
+
+[![NPM Package](https://img.shields.io/npm/v/openzeppelin-eth.svg?style=flat-square)](https://www.npmjs.org/package/openzeppelin-eth)
+[![Build Status](https://img.shields.io/travis/OpenZeppelin/openzeppelin-eth.svg?branch=master&style=flat-square)](https://travis-ci.org/OpenZeppelin/openzeppelin-eth)
 
 **OpenZeppelin is a library for secure smart contract development.** It provides implementations of standards like ERC20 and ERC721 which you can deploy as-is or extend to suit your needs, as well as Solidity components to build custom contracts and more complex decentralized systems.
 
+This fork of OpenZeppelin is set up as a **reusable EVM Package**. It is deployed to the kovan, rinkeby, and ropsten test networks, as well as to the main Ethereum network. You can reuse any of the pre-deployed on-chain contracts by simply linking to them using [ZeppelinOS](https://github.com/zeppelinos/zos), or reuse their Solidity source code as with the vanilla version of OpenZeppelin.
+
 ## Install
 
 ```
-npm install openzeppelin-solidity
+npm install openzeppelin-eth
 ```
 
-## Usage
+## Pre-deployed contracts
 
-To write your custom contracts, import ours and extend them through inheritance.
-
-```solidity
-import 'openzeppelin-solidity/contracts/token/ERC721/ERC721.sol';
-import 'openzeppelin-solidity/contracts/token/ERC721/ERC721Mintable.sol';
-
-contract MyNFT is ERC721, ERC721Mintable {
-}
-```
-
-> You need an ethereum development framework for the above import statements to work! Check out these guides for [Truffle] or [Embark].
-
-On our site you will find a few [guides] to learn about the diferent parts of OpenZeppelin, as well as [documentation for the API][API docs]. Keep in mind that the API docs are work in progress, and don’t hesitate to ask questions in [our Slack][Slack].
-
-## Security
-
-OpenZeppelin the project is maintained by [Zeppelin] the company, and developed following our high standards for code quality and security. OpenZeppelin is meant to provide tested and community-audited code, but please use common sense when doing anything that deals with real money! We take no responsibility for your implementation decisions and any security problems you might experience.
-
-The core development principles and strategies that OpenZeppelin is based on include: security in depth, simple and modular code, clarity-driven naming conventions, comprehensive unit testing, pre-and-post-condition sanity checks, code consistency, and regular audits.
-
-Please report any security issues you find to security@openzeppelin.org.
-
-## Contribute
-
-OpenZeppelin exists thanks to its contributors. There are many ways you can participate and help build high quality software. Check out the [contribution guide]!
+- StandaloneERC20
+- StandaloneERC721
+- TokenVesting
+- PaymentSplitter
 
 ## License
 
 OpenZeppelin is released under the [MIT License](LICENSE).
 
-
-[API docs]: https://openzeppelin.org/api/docs/token_ERC721_ERC721BasicToken.html
-[guides]: https://openzeppelin.org/api/docs/get-started.html
 [Slack]: https://slack.openzeppelin.org
 [Zeppelin]: https://zeppelin.solutions
-[contribution guide]: CONTRIBUTING.md
-[Truffle]: https://truffleframework.com/docs/truffle/quickstart
-[Embark]: https://embark.status.im/docs/quick_start.html

contracts/access/roles/CapperRole.sol

@@ -1,9 +1,10 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../Roles.sol";
 
 
-contract CapperRole {
+contract CapperRole is Initializable {
   using Roles for Roles.Role;
 
   event CapperAdded(address indexed account);
@@ -11,8 +12,10 @@ contract CapperRole {
 
   Roles.Role private cappers;
 
-  constructor() public {
-    cappers.add(msg.sender);
+  function initialize(address sender) public initializer {
+    if (!isCapper(sender)) {
+      _addCapper(sender);
+    }
   }
 
   modifier onlyCapper() {
@@ -25,16 +28,22 @@ contract CapperRole {
   }
 
   function addCapper(address account) public onlyCapper {
-    cappers.add(account);
-    emit CapperAdded(account);
+    _addCapper(account);
   }
 
   function renounceCapper() public {
-    cappers.remove(msg.sender);
+    _removeCapper(msg.sender);
+  }
+
+  function _addCapper(address account) internal {
+    cappers.add(account);
+    emit CapperAdded(account);
   }
 
   function _removeCapper(address account) internal {
     cappers.remove(account);
     emit CapperRemoved(account);
   }
+
+  uint256[50] private ______gap;
 }

contracts/access/roles/MinterRole.sol

@@ -1,9 +1,10 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../Roles.sol";
 
 
-contract MinterRole {
+contract MinterRole is Initializable {
   using Roles for Roles.Role;
 
   event MinterAdded(address indexed account);
@@ -11,8 +12,10 @@ contract MinterRole {
 
   Roles.Role private minters;
 
-  constructor() public {
-    minters.add(msg.sender);
+  function initialize(address sender) public initializer {
+    if (!isMinter(sender)) {
+      _addMinter(sender);
+    }
   }
 
   modifier onlyMinter() {
@@ -25,16 +28,22 @@ contract MinterRole {
   }
 
   function addMinter(address account) public onlyMinter {
-    minters.add(account);
-    emit MinterAdded(account);
+    _addMinter(account);
   }
 
   function renounceMinter() public {
-    minters.remove(msg.sender);
+    _removeMinter(msg.sender);
+  }
+
+  function _addMinter(address account) internal {
+    minters.add(account);
+    emit MinterAdded(account);
   }
 
   function _removeMinter(address account) internal {
     minters.remove(account);
     emit MinterRemoved(account);
   }
+
+  uint256[50] private ______gap;
 }

contracts/access/roles/PauserRole.sol

@@ -1,9 +1,10 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../Roles.sol";
 
 
-contract PauserRole {
+contract PauserRole is Initializable {
   using Roles for Roles.Role;
 
   event PauserAdded(address indexed account);
@@ -11,8 +12,10 @@ contract PauserRole {
 
   Roles.Role private pausers;
 
-  constructor() public {
-    pausers.add(msg.sender);
+  function initialize(address sender) public initializer {
+    if (!isPauser(sender)) {
+      _addPauser(sender);
+    }
   }
 
   modifier onlyPauser() {
@@ -25,16 +28,22 @@ contract PauserRole {
   }
 
   function addPauser(address account) public onlyPauser {
-    pausers.add(account);
-    emit PauserAdded(account);
+    _addPauser(account);
   }
 
   function renouncePauser() public {
-    pausers.remove(msg.sender);
+    _removePauser(msg.sender);
+  }
+
+  function _addPauser(address account) internal {
+    pausers.add(account);
+    emit PauserAdded(account);
   }
 
   function _removePauser(address account) internal {
     pausers.remove(account);
     emit PauserRemoved(account);
   }
+
+  uint256[50] private ______gap;
 }

contracts/access/roles/SignerRole.sol

@@ -1,9 +1,10 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../Roles.sol";
 
 
-contract SignerRole {
+contract SignerRole is Initializable {
   using Roles for Roles.Role;
 
   event SignerAdded(address indexed account);
@@ -11,8 +12,10 @@ contract SignerRole {
 
   Roles.Role private signers;
 
-  constructor() public {
-    signers.add(msg.sender);
+  function initialize(address sender) public initializer {
+    if (!isSigner(sender)) {
+      _addSigner(sender);
+    }
   }
 
   modifier onlySigner() {
@@ -25,16 +28,22 @@ contract SignerRole {
   }
 
   function addSigner(address account) public onlySigner {
-    signers.add(account);
-    emit SignerAdded(account);
+    _addSigner(account);
   }
 
   function renounceSigner() public {
-    signers.remove(msg.sender);
+    _removeSigner(msg.sender);
+  }
+
+  function _addSigner(address account) internal {
+    signers.add(account);
+    emit SignerAdded(account);
   }
 
   function _removeSigner(address account) internal {
     signers.remove(account);
     emit SignerRemoved(account);
   }
+
+  uint256[50] private ______gap;
 }

contracts/bounties/BreakInvariantBounty.sol

@@ -1,87 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-import "../payment/PullPayment.sol";
-import "../ownership/Ownable.sol";
-
-
-/**
- * @title BreakInvariantBounty
- * @dev This bounty will pay out to a researcher if they break invariant logic of the contract.
- */
-contract BreakInvariantBounty is PullPayment, Ownable {
-  bool private _claimed;
-  mapping(address => address) private _researchers;
-
-  event TargetCreated(address createdAddress);
-
-  /**
-   * @dev Fallback function allowing the contract to receive funds, if they haven't already been claimed.
-   */
-  function() external payable {
-    require(!_claimed);
-  }
-
-  /**
-   * @dev Determine if the bounty was claimed.
-   * @return true if the bounty was claimed, false otherwise.
-   */
-  function claimed() public view returns(bool) {
-    return _claimed;
-  }
-
-  /**
-   * @dev Create and deploy the target contract (extension of Target contract), and sets the
-   * msg.sender as a researcher
-   * @return A target contract
-   */
-  function createTarget() public returns(Target) {
-    Target target = Target(_deployContract());
-    _researchers[target] = msg.sender;
-    emit TargetCreated(target);
-    return target;
-  }
-
-  /**
-   * @dev Transfers the contract funds to the researcher that proved the contract is broken.
-   * @param target contract
-   */
-  function claim(Target target) public {
-    address researcher = _researchers[target];
-    require(researcher != address(0));
-    // Check Target contract invariants
-    require(!target.checkInvariant());
-    _asyncTransfer(researcher, address(this).balance);
-    _claimed = true;
-  }
-
-  /**
-   * @dev Transfers the current balance to the owner and terminates the contract.
-   */
-  function destroy() public onlyOwner {
-    selfdestruct(owner());
-  }
-
-  /**
-   * @dev Internal function to deploy the target contract.
-   * @return A target contract address
-   */
-  function _deployContract() internal returns(address);
-
-}
-
-
-/**
- * @title Target
- * @dev Your main contract should inherit from this class and implement the checkInvariant method.
- */
-contract Target {
-
-   /**
-    * @dev Checks all values a contract assumes to be true all the time. If this function returns
-    * false, the contract is broken in some way and is in an inconsistent state.
-    * In order to win the bounty, security researchers will try to cause this broken state.
-    * @return True if all invariant values are correct, false otherwise.
-    */
-  function checkInvariant() public returns(bool);
-}

contracts/crowdsale/Crowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../token/ERC20/IERC20.sol";
 import "../math/SafeMath.sol";
 import "../token/ERC20/SafeERC20.sol";
@@ -17,7 +18,7 @@ import "../token/ERC20/SafeERC20.sol";
  * the methods to add functionality. Consider using 'super' where appropriate to concatenate
  * behavior.
  */
-contract Crowdsale {
+contract Crowdsale is Initializable {
   using SafeMath for uint256;
   using SafeERC20 for IERC20;
 
@@ -58,7 +59,7 @@ contract Crowdsale {
    * @param wallet Address where collected funds will be forwarded to
    * @param token Address of the token being sold
    */
-  constructor(uint256 rate, address wallet, IERC20 token) public {
+  function initialize(uint256 rate, address wallet, IERC20 token) public initializer {
     require(rate > 0);
     require(wallet != address(0));
     require(token != address(0));
@@ -140,6 +141,10 @@ contract Crowdsale {
   // Internal interface (extensible)
   // -----------------------------------------
 
+  function _hasBeenInitialized() internal view returns (bool) {
+    return ((_rate > 0) && (_wallet != address(0)) && (_token != address(0)));
+  }
+
   /**
    * @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met. Use `super` in contracts that inherit from Crowdsale to extend their validations.
    * Example from CappedCrowdsale.sol's _preValidatePurchase method:
@@ -231,4 +236,6 @@ contract Crowdsale {
   function _forwardFunds() internal {
     _wallet.transfer(msg.value);
   }
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/distribution/FinalizableCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../math/SafeMath.sol";
 import "../validation/TimedCrowdsale.sol";
 
@@ -9,7 +10,7 @@ import "../validation/TimedCrowdsale.sol";
  * @dev Extension of Crowdsale with a one-off finalization action, where one
  * can do extra work after finishing.
  */
-contract FinalizableCrowdsale is TimedCrowdsale {
+contract FinalizableCrowdsale is Initializable, TimedCrowdsale {
   using SafeMath for uint256;
 
   bool private _finalized = false;
@@ -45,4 +46,6 @@ contract FinalizableCrowdsale is TimedCrowdsale {
   function _finalization() internal {
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/distribution/PostDeliveryCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../validation/TimedCrowdsale.sol";
 import "../../token/ERC20/IERC20.sol";
 import "../../math/SafeMath.sol";
@@ -9,7 +10,7 @@ import "../../math/SafeMath.sol";
  * @title PostDeliveryCrowdsale
  * @dev Crowdsale that locks tokens from withdrawal until it ends.
  */
-contract PostDeliveryCrowdsale is TimedCrowdsale {
+contract PostDeliveryCrowdsale is Initializable, TimedCrowdsale {
   using SafeMath for uint256;
 
   mapping(address => uint256) private _balances;
@@ -47,4 +48,6 @@ contract PostDeliveryCrowdsale is TimedCrowdsale {
     _balances[beneficiary] = _balances[beneficiary].add(tokenAmount);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/distribution/RefundableCrowdsale.sol

@@ -1,6 +1,7 @@
 pragma solidity ^0.4.24;
 
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../math/SafeMath.sol";
 import "./FinalizableCrowdsale.sol";
 import "../../payment/RefundEscrow.sol";
@@ -11,7 +12,7 @@ import "../../payment/RefundEscrow.sol";
  * @dev Extension of Crowdsale contract that adds a funding goal, and
  * the possibility of users getting a refund if goal is not met.
  */
-contract RefundableCrowdsale is FinalizableCrowdsale {
+contract RefundableCrowdsale is Initializable, FinalizableCrowdsale {
   using SafeMath for uint256;
 
   // minimum amount of funds to be raised in weis
@@ -24,9 +25,18 @@ contract RefundableCrowdsale is FinalizableCrowdsale {
    * @dev Constructor, creates RefundEscrow.
    * @param goal Funding goal
    */
-  constructor(uint256 goal) public {
+  function initialize(uint256 goal) public initializer {
+    // FinalizableCrowdsale depends on TimedCrowdsale
+    assert(TimedCrowdsale._hasBeenInitialized());
+
     require(goal > 0);
-    _escrow = new RefundEscrow(wallet());
+
+    // conditional added to make initializer idempotent in case of diamond inheritance
+    if (address(_escrow) == address(0)) {
+      _escrow = new RefundEscrow();
+      _escrow.initialize(wallet(), address(this));
+    }
+
     _goal = goal;
   }
 
@@ -77,4 +87,6 @@ contract RefundableCrowdsale is FinalizableCrowdsale {
     _escrow.deposit.value(msg.value)(msg.sender);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/emission/AllowanceCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../Crowdsale.sol";
 import "../../token/ERC20/IERC20.sol";
 import "../../token/ERC20/SafeERC20.sol";
@@ -10,7 +11,7 @@ import "../../math/SafeMath.sol";
  * @title AllowanceCrowdsale
  * @dev Extension of Crowdsale where tokens are held by a wallet, which approves an allowance to the crowdsale.
  */
-contract AllowanceCrowdsale is Crowdsale {
+contract AllowanceCrowdsale is Initializable, Crowdsale {
   using SafeMath for uint256;
   using SafeERC20 for IERC20;
 
@@ -20,7 +21,9 @@ contract AllowanceCrowdsale is Crowdsale {
    * @dev Constructor, takes token wallet address.
    * @param tokenWallet Address holding the tokens, which has approved allowance to the crowdsale
    */
-  constructor(address tokenWallet) public {
+  function initialize(address tokenWallet) public initializer {
+    assert(Crowdsale._hasBeenInitialized());
+
     require(tokenWallet != address(0));
     _tokenWallet = tokenWallet;
   }
@@ -53,4 +56,6 @@ contract AllowanceCrowdsale is Crowdsale {
   {
     token().safeTransferFrom(_tokenWallet, beneficiary, tokenAmount);
   }
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/emission/MintedCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../Crowdsale.sol";
 import "../../token/ERC20/ERC20Mintable.sol";
 
@@ -9,7 +10,7 @@ import "../../token/ERC20/ERC20Mintable.sol";
  * @dev Extension of Crowdsale contract whose tokens are minted in each purchase.
  * Token ownership should be transferred to MintedCrowdsale for minting.
  */
-contract MintedCrowdsale is Crowdsale {
+contract MintedCrowdsale is Initializable, Crowdsale {
 
   /**
    * @dev Overrides delivery by minting tokens upon purchase.
@@ -26,4 +27,6 @@ contract MintedCrowdsale is Crowdsale {
     require(
       ERC20Mintable(address(token())).mint(beneficiary, tokenAmount));
   }
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/price/IncreasingPriceCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../validation/TimedCrowdsale.sol";
 import "../../math/SafeMath.sol";
 
@@ -10,7 +11,7 @@ import "../../math/SafeMath.sol";
  * Note that what should be provided to the constructor is the initial and final _rates_, that is,
  * the amount of tokens per wei contributed. Thus, the initial rate must be greater than the final rate.
  */
-contract IncreasingPriceCrowdsale is TimedCrowdsale {
+contract IncreasingPriceCrowdsale is Initializable, TimedCrowdsale {
   using SafeMath for uint256;
 
   uint256 private _initialRate;
@@ -21,7 +22,9 @@ contract IncreasingPriceCrowdsale is TimedCrowdsale {
    * @param initialRate Number of tokens a buyer gets per wei at the start of the crowdsale
    * @param finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
    */
-  constructor(uint256 initialRate, uint256 finalRate) public {
+  function initialize(uint256 initialRate, uint256 finalRate) public initializer {
+    assert(TimedCrowdsale._hasBeenInitialized());
+
     require(finalRate > 0);
     require(initialRate >= finalRate);
     _initialRate = initialRate;
@@ -67,4 +70,6 @@ contract IncreasingPriceCrowdsale is TimedCrowdsale {
     return currentRate.mul(weiAmount);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/validation/CappedCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
 
@@ -8,7 +9,7 @@ import "../Crowdsale.sol";
  * @title CappedCrowdsale
  * @dev Crowdsale with a limit for total contributions.
  */
-contract CappedCrowdsale is Crowdsale {
+contract CappedCrowdsale is Initializable, Crowdsale {
   using SafeMath for uint256;
 
   uint256 private _cap;
@@ -17,7 +18,9 @@ contract CappedCrowdsale is Crowdsale {
    * @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
    * @param cap Max amount of wei to be contributed
    */
-  constructor(uint256 cap) public {
+  function initialize(uint256 cap) public initializer {
+    assert(Crowdsale._hasBeenInitialized());
+
     require(cap > 0);
     _cap = cap;
   }
@@ -52,4 +55,6 @@ contract CappedCrowdsale is Crowdsale {
     require(weiRaised().add(weiAmount) <= _cap);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/validation/IndividuallyCappedCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
 import "../../access/roles/CapperRole.sol";
@@ -9,12 +10,18 @@ import "../../access/roles/CapperRole.sol";
  * @title IndividuallyCappedCrowdsale
  * @dev Crowdsale with per-beneficiary caps.
  */
-contract IndividuallyCappedCrowdsale is Crowdsale, CapperRole {
+contract IndividuallyCappedCrowdsale is Initializable, Crowdsale, CapperRole {
   using SafeMath for uint256;
 
   mapping(address => uint256) private _contributions;
   mapping(address => uint256) private _caps;
 
+  function initialize(address sender) public initializer {
+    assert(Crowdsale._hasBeenInitialized());
+
+    CapperRole.initialize(sender);
+  }
+
   /**
    * @dev Sets a specific beneficiary's maximum contribution.
    * @param beneficiary Address to be capped
@@ -76,4 +83,6 @@ contract IndividuallyCappedCrowdsale is Crowdsale, CapperRole {
       weiAmount);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/crowdsale/validation/TimedCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
 
@@ -8,7 +9,7 @@ import "../Crowdsale.sol";
  * @title TimedCrowdsale
  * @dev Crowdsale accepting contributions only within a time frame.
  */
-contract TimedCrowdsale is Crowdsale {
+contract TimedCrowdsale is Initializable, Crowdsale {
   using SafeMath for uint256;
 
   uint256 private _openingTime;
@@ -27,7 +28,9 @@ contract TimedCrowdsale is Crowdsale {
    * @param openingTime Crowdsale opening time
    * @param closingTime Crowdsale closing time
    */
-  constructor(uint256 openingTime, uint256 closingTime) public {
+  function initialize(uint256 openingTime, uint256 closingTime) public initializer {
+    assert(Crowdsale._hasBeenInitialized());
+
     // solium-disable-next-line security/no-block-members
     require(openingTime >= block.timestamp);
     require(closingTime >= openingTime);
@@ -67,6 +70,10 @@ contract TimedCrowdsale is Crowdsale {
     return block.timestamp > _closingTime;
   }
 
+  function _hasBeenInitialized() internal view returns (bool) {
+    return ((_openingTime > 0) && (_closingTime > 0));
+  }
+
   /**
    * @dev Extend parent behavior requiring to be within contributing period
    * @param beneficiary Token purchaser
@@ -82,4 +89,6 @@ contract TimedCrowdsale is Crowdsale {
     super._preValidatePurchase(beneficiary, weiAmount);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/drafts/Counter.sol

@@ -2,28 +2,28 @@ pragma solidity ^0.4.24;
 
 
 /**
- * @title AutoIncrementing
+ * @title Counter
  * @author Matt Condon (@shrugs)
- * @dev Provides an auto-incrementing uint256 id acquired by the `Counter#nextId` getter.
+ * @dev Provides an incrementing uint256 id acquired by the `Counter#next` getter.
  * Use this for issuing ERC721 ids or keeping track of request ids, anything you want, really.
  *
- * Include with `using AutoIncrementing for AutoIncrementing.Counter;`
+ * Include with `using Counter for Counter.Counter;`
  * @notice Does not allow an Id of 0, which is popularly used to signify a null state in solidity.
  * Does not protect from overflows, but if you have 2^256 ids, you have other problems.
  * (But actually, it's generally impossible to increment a counter this many times, energy wise
  * so it's not something you have to worry about.)
  */
-library AutoIncrementing {
+library Counter {
 
   struct Counter {
-    uint256 prevId; // default: 0
+    uint256 current; // default: 0
   }
 
-  function nextId(Counter storage counter)
+  function next(Counter storage index)
     internal
     returns (uint256)
   {
-    counter.prevId = counter.prevId + 1;
-    return counter.prevId;
+    index.current += 1;
+    return index.current;
   }
 }

contracts/drafts/ERC1046/TokenMetadata.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../token/ERC20/IERC20.sol";
 
 
@@ -9,16 +10,19 @@ import "../../token/ERC20/IERC20.sol";
  * @dev tokenURI must respond with a URI that implements https://eips.ethereum.org/EIPS/eip-1047
  * @dev TODO - update https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC721/IERC721.sol#L17 when 1046 is finalized
  */
-contract ERC20TokenMetadata is IERC20 {
+contract ERC20TokenMetadata is Initializable, IERC20 {
   function tokenURI() external view returns (string);
+
+  uint256[50] private ______gap;
 }
 
 
-contract ERC20WithMetadata is ERC20TokenMetadata {
+contract ERC20WithMetadata is Initializable, ERC20TokenMetadata {
   string private _tokenURI = "";
 
-  constructor(string tokenURI)
+  function initialize(string tokenURI)
     public
+    initializer
   {
     _tokenURI = tokenURI;
   }
@@ -26,4 +30,6 @@ contract ERC20WithMetadata is ERC20TokenMetadata {
   function tokenURI() external view returns (string) {
     return _tokenURI;
   }
+
+  uint256[50] private ______gap;
 }

contracts/drafts/ERC20Migrator.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../token/ERC20/IERC20.sol";
 import "../token/ERC20/ERC20Mintable.sol";
 import "../token/ERC20/SafeERC20.sol";
@@ -32,7 +33,7 @@ import "../math/Math.sol";
  * await migrator.beginMigration(newToken.address);
  * ```
  */
-contract ERC20Migrator {
+contract ERC20Migrator is Initializable {
   using SafeERC20 for IERC20;
 
   /// Address of the old token contract
@@ -44,7 +45,7 @@ contract ERC20Migrator {
   /**
    * @param legacyToken address of the old token contract
    */
-  constructor(IERC20 legacyToken) public {
+  function initialize(IERC20 legacyToken) public initializer {
     require(legacyToken != address(0));
     _legacyToken = legacyToken;
   }
@@ -98,4 +99,6 @@ contract ERC20Migrator {
     uint256 amount = Math.min(balance, allowance);
     migrate(account, amount);
   }
+
+  uint256[50] private ______gap;
 }

contracts/drafts/SignatureBouncer.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../access/roles/SignerRole.sol";
 import "../cryptography/ECDSA.sol";
 
@@ -28,7 +29,7 @@ import "../cryptography/ECDSA.sol";
  * Also non fixed sized parameters make constructing the data in the signature
  * much more complex. See https://ethereum.stackexchange.com/a/50616 for more details.
  */
-contract SignatureBouncer is SignerRole {
+contract SignatureBouncer is Initializable, SignerRole {
   using ECDSA for bytes32;
 
   // Function selectors are 4 bytes long, as documented in
@@ -64,6 +65,10 @@ contract SignatureBouncer is SignerRole {
     _;
   }
 
+  function initialize(address sender) public initializer {
+    SignerRole.initialize(sender);
+  }
+
   /**
    * @dev is the signature of `this + sender` from a signer?
    * @return bool
@@ -135,4 +140,6 @@ contract SignatureBouncer is SignerRole {
 
     return signer != address(0) && isSigner(signer);
   }
+
+  uint256[50] private ______gap;
 }

contracts/drafts/TokenVesting.sol

@@ -2,6 +2,7 @@
 
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../token/ERC20/SafeERC20.sol";
 import "../ownership/Ownable.sol";
 import "../math/SafeMath.sol";
@@ -13,7 +14,7 @@ import "../math/SafeMath.sol";
  * typical vesting scheme, with a cliff and vesting period. Optionally revocable by the
  * owner.
  */
-contract TokenVesting is Ownable {
+contract TokenVesting is Initializable, Ownable {
   using SafeMath for uint256;
   using SafeERC20 for IERC20;
 
@@ -42,15 +43,19 @@ contract TokenVesting is Ownable {
    * @param duration duration in seconds of the period in which the tokens will vest
    * @param revocable whether the vesting is revocable or not
    */
-  constructor(
+  function initialize(
     address beneficiary,
     uint256 start,
     uint256 cliffDuration,
     uint256 duration,
-    bool revocable
+    bool revocable,
+    address sender
   )
     public
+    initializer
   {
+    Ownable.initialize(sender);
+
     require(beneficiary != address(0));
     require(cliffDuration <= duration);
 
@@ -171,4 +176,6 @@ contract TokenVesting is Ownable {
       return totalBalance.mul(block.timestamp.sub(_start)).div(_duration);
     }
   }
+
+  uint256[50] private ______gap;
 }

contracts/examples/SampleCrowdsale.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../crowdsale/validation/CappedCrowdsale.sol";
 import "../crowdsale/distribution/RefundableCrowdsale.sol";
 import "../crowdsale/emission/MintedCrowdsale.sol";
@@ -11,11 +12,21 @@ import "../token/ERC20/ERC20Mintable.sol";
  * @dev Very simple ERC20 Token that can be minted.
  * It is meant to be used in a crowdsale contract.
  */
-contract SampleCrowdsaleToken is ERC20Mintable {
+contract SampleCrowdsaleToken is Initializable, ERC20Mintable {
 
-  string public constant name = "Sample Crowdsale Token";
-  string public constant symbol = "SCT";
-  uint8 public constant decimals = 18;
+  string public name;
+  string public symbol;
+  uint8 public decimals;
+
+  function initialize(address sender) public initializer {
+    ERC20Mintable.initialize(sender);
+
+    name = "Sample Crowdsale Token";
+    symbol = "SCT";
+    decimals = 18;
+  }
+
+  uint256[50] private ______gap;
 }
 
 
@@ -35,9 +46,9 @@ contract SampleCrowdsaleToken is ERC20Mintable {
 // https://github.com/duaraghav8/Solium/issues/205
 // --elopio - 2018-05-10
 // solium-disable-next-line max-len
-contract SampleCrowdsale is CappedCrowdsale, RefundableCrowdsale, MintedCrowdsale {
+contract SampleCrowdsale is Initializable, Crowdsale, CappedCrowdsale, RefundableCrowdsale, MintedCrowdsale {
 
-  constructor(
+  function initialize(
     uint256 openingTime,
     uint256 closingTime,
     uint256 rate,
@@ -47,13 +58,17 @@ contract SampleCrowdsale is CappedCrowdsale, RefundableCrowdsale, MintedCrowdsal
     uint256 goal
   )
     public
-    Crowdsale(rate, wallet, token)
-    CappedCrowdsale(cap)
-    TimedCrowdsale(openingTime, closingTime)
-    RefundableCrowdsale(goal)
+    initializer
   {
+    Crowdsale.initialize(rate, wallet, token);
+    CappedCrowdsale.initialize(cap);
+    TimedCrowdsale.initialize(openingTime, closingTime);
+    RefundableCrowdsale.initialize(goal);
+
     //As goal needs to be met for a successful crowdsale
     //the value needs to less or equal than a cap which is limit for accepted funds
     require(goal <= cap);
   }
+
+  uint256[50] private ______gap;
 }

contracts/examples/SimpleToken.sol

@@ -1,6 +1,7 @@
 pragma solidity ^0.4.24;
 
 
+import "zos-lib/contracts/Initializable.sol";
 import "../token/ERC20/ERC20.sol";
 
 
@@ -10,7 +11,7 @@ import "../token/ERC20/ERC20.sol";
  * Note they can later distribute these tokens as they wish using `transfer` and other
  * `ERC20` functions.
  */
-contract SimpleToken is ERC20 {
+contract SimpleToken is Initializable, ERC20 {
 
   string public constant name = "SimpleToken";
   string public constant symbol = "SIM";
@@ -19,10 +20,12 @@ contract SimpleToken is ERC20 {
   uint256 public constant INITIAL_SUPPLY = 10000 * (10 ** uint256(decimals));
 
   /**
-   * @dev Constructor that gives msg.sender all of existing tokens.
+   * @dev Constructor that gives sender all of existing tokens.
    */
-  constructor() public {
-    _mint(msg.sender, INITIAL_SUPPLY);
+  function initialize(address sender) public initializer {
+    _mint(sender, INITIAL_SUPPLY);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/examples/StandardToken.sol

@@ -0,0 +1,42 @@
+pragma solidity ^0.4.24;
+
+import "zos-lib/contracts/Initializable.sol";
+import "../token/ERC20/ERC20Detailed.sol";
+import "../token/ERC20/ERC20Mintable.sol";
+import "../token/ERC20/ERC20Pausable.sol";
+
+
+/**
+ * @title Standard ERC20 token, with minting and pause functionality.
+ *
+ */
+contract StandardToken is Initializable, ERC20Detailed, ERC20Mintable, ERC20Pausable {
+  function initialize(
+    string name, string symbol, uint8 decimals, uint256 initialSupply, address initialHolder, 
+    address[] minters, address[] pausers
+  ) public initializer {
+    ERC20Detailed.initialize(name, symbol, decimals);
+
+    // Mint the initial supply
+    if (initialSupply > 0) { // To allow passing a null address when not doing any initial supply
+      _mint(initialHolder, initialSupply);
+    }
+
+    // Initialize the minter and pauser roles, and renounce them
+    ERC20Mintable.initialize(address(this));
+    renounceMinter();
+
+    ERC20Pausable.initialize(address(this));
+    renouncePauser();
+
+    // Add the requested minters and pausers (this can be done after renouncing since
+    // these are the internal calls)
+    for (uint256 i = 0; i < minters.length; ++i) {
+      _addMinter(minters[i]);
+    }
+
+    for (i = 0; i < pausers.length; ++i) {
+      _addPauser(pausers[i]);
+    }
+  }
+}

contracts/introspection/ERC165.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./IERC165.sol";
 
 
@@ -8,7 +9,7 @@ import "./IERC165.sol";
  * @author Matt Condon (@shrugs)
  * @dev Implements ERC165 using a lookup table.
  */
-contract ERC165 is IERC165 {
+contract ERC165 is Initializable, IERC165 {
 
   bytes4 private constant _InterfaceId_ERC165 = 0x01ffc9a7;
   /**
@@ -25,8 +26,9 @@ contract ERC165 is IERC165 {
    * @dev A contract implementing SupportsInterfaceWithLookup
    * implement ERC165 itself
    */
-  constructor()
+  function initialize()
     public
+    initializer
   {
     _registerInterface(_InterfaceId_ERC165);
   }
@@ -35,7 +37,7 @@ contract ERC165 is IERC165 {
    * @dev implement supportsInterface(bytes4) using a lookup table
    */
   function supportsInterface(bytes4 interfaceId)
-    external
+    public
     view
     returns (bool)
   {
@@ -51,4 +53,6 @@ contract ERC165 is IERC165 {
     require(interfaceId != 0xffffffff);
     _supportedInterfaces[interfaceId] = true;
   }
+
+  uint256[50] private ______gap;
 }

contracts/lifecycle/Pausable.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../access/roles/PauserRole.sol";
 
 
@@ -7,12 +8,15 @@ import "../access/roles/PauserRole.sol";
  * @title Pausable
  * @dev Base contract which allows children to implement an emergency stop mechanism.
  */
-contract Pausable is PauserRole {
+contract Pausable is Initializable, PauserRole {
   event Paused();
   event Unpaused();
 
   bool private _paused = false;
 
+  function initialize(address sender) public initializer {
+    PauserRole.initialize(sender);
+  }
 
   /**
    * @return true if the contract is paused, false otherwise.
@@ -52,4 +56,6 @@ contract Pausable is PauserRole {
     _paused = false;
     emit Unpaused();
   }
+
+  uint256[50] private ______gap;
 }

contracts/mocks/AllowanceCrowdsaleImpl.sol

@@ -13,9 +13,9 @@ contract AllowanceCrowdsaleImpl is AllowanceCrowdsale {
     address tokenWallet
   )
     public
-    Crowdsale(rate, wallet, token)
-    AllowanceCrowdsale(tokenWallet)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    AllowanceCrowdsale.initialize(tokenWallet);
   }
 
 }

contracts/mocks/AutoIncrementingImpl.sol

@@ -1,21 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../utils/AutoIncrementing.sol";
-
-
-contract AutoIncrementingImpl {
-  using AutoIncrementing for AutoIncrementing.Counter;
-
-  uint256 public theId;
-
-  // use whatever key you want to track your counters
-  mapping(string => AutoIncrementing.Counter) private _counters;
-
-  function doThing(string key)
-    public
-    returns (uint256)
-  {
-    theId = _counters[key].nextId();
-    return theId;
-  }
-}

contracts/mocks/CappedCrowdsaleImpl.sol

@@ -13,9 +13,9 @@ contract CappedCrowdsaleImpl is CappedCrowdsale {
     uint256 cap
   )
     public
-    Crowdsale(rate, wallet, token)
-    CappedCrowdsale(cap)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    CappedCrowdsale.initialize(cap);
   }
 
 }

contracts/mocks/CapperRoleMock.sol

@@ -4,6 +4,10 @@ import "../access/roles/CapperRole.sol";
 
 
 contract CapperRoleMock is CapperRole {
+  constructor() public {
+    CapperRole.initialize(msg.sender);
+  }
+
   function removeCapper(address account) public {
     _removeCapper(account);
   }

contracts/mocks/ConditionalEscrowMock.sol

@@ -1,6 +1,5 @@
 pragma solidity ^0.4.24;
 
-
 import "../payment/ConditionalEscrow.sol";
 
 
@@ -8,6 +7,10 @@ import "../payment/ConditionalEscrow.sol";
 contract ConditionalEscrowMock is ConditionalEscrow {
   mapping(address => bool) private _allowed;
 
+  constructor() public {
+    ConditionalEscrow.initialize(msg.sender);
+  }
+
   function setAllowed(address payee, bool allowed) public {
     _allowed[payee] = allowed;
   }

contracts/mocks/CounterImpl.sol

@@ -0,0 +1,21 @@
+pragma solidity ^0.4.24;
+
+import "../drafts/Counter.sol";
+
+
+contract CounterImpl {
+  using Counter for Counter.Counter;
+
+  uint256 public theId;
+
+  // use whatever key you want to track your counters
+  mapping(string => Counter.Counter) private _counters;
+
+  function doThing(string key)
+    public
+    returns (uint256)
+  {
+    theId = _counters[key].next();
+    return theId;
+  }
+}

contracts/mocks/CrowdsaleMock.sol

@@ -0,0 +1,10 @@
+pragma solidity ^0.4.24;
+
+import "../crowdsale/Crowdsale.sol";
+
+
+contract CrowdsaleMock is Crowdsale {
+  constructor(uint256 rate, address wallet, IERC20 token) public {
+    Crowdsale.initialize(rate, wallet, token);
+  }
+}

contracts/mocks/DetailedERC20Mock.sol

@@ -10,7 +10,8 @@ contract ERC20DetailedMock is ERC20, ERC20Detailed {
     string symbol,
     uint8 decimals
   )
-    ERC20Detailed(name, symbol, decimals)
     public
-  {}
+  {
+    ERC20Detailed.initialize(name, symbol, decimals);
+  }
 }

contracts/mocks/ECDSAMock.sol

@@ -1,6 +1,5 @@
 pragma solidity ^0.4.24;
 
-
 import "../cryptography/ECDSA.sol";
 
 

contracts/mocks/ERC165Mock.sol

@@ -4,6 +4,10 @@ import "../introspection/ERC165.sol";
 
 
 contract ERC165Mock is ERC165 {
+  constructor() public {
+    ERC165.initialize();
+  }
+
   function registerInterface(bytes4 interfaceId)
     public
   {

contracts/mocks/ERC20CappedMock.sol

@@ -0,0 +1,13 @@
+pragma solidity ^0.4.24;
+
+import "../token/ERC20/ERC20Capped.sol";
+import "./MinterRoleMock.sol";
+
+
+contract ERC20CappedMock is ERC20Capped, MinterRoleMock {
+
+  constructor(uint256 cap) public {
+    ERC20Capped.initialize(cap, msg.sender);
+  }
+
+}

contracts/mocks/ERC20MigratorMock.sol

@@ -0,0 +1,12 @@
+pragma solidity ^0.4.24;
+
+import "../drafts/ERC20Migrator.sol";
+
+
+contract ERC20MigratorMock is ERC20Migrator {
+
+  constructor(IERC20 legacyToken) public {
+    ERC20Migrator.initialize(legacyToken);
+  }
+
+}

contracts/mocks/ERC20MintableMock.sol

@@ -5,4 +5,8 @@ import "./MinterRoleMock.sol";
 
 
 contract ERC20MintableMock is ERC20Mintable, MinterRoleMock {
+
+  constructor() public {
+    ERC20Mintable.initialize(msg.sender);
+  }
 }

contracts/mocks/ERC20PausableMock.sol

@@ -8,6 +8,8 @@ import "./PauserRoleMock.sol";
 contract ERC20PausableMock is ERC20Pausable, PauserRoleMock {
 
   constructor(address initialAccount, uint initialBalance) public {
+    ERC20Pausable.initialize(msg.sender);
+
     _mint(initialAccount, initialBalance);
   }
 

contracts/mocks/ERC20WithMetadataMock.sol

@@ -5,8 +5,7 @@ import "../drafts/ERC1046/TokenMetadata.sol";
 
 
 contract ERC20WithMetadataMock is ERC20, ERC20WithMetadata {
-  constructor(string tokenURI) public
-    ERC20WithMetadata(tokenURI)
-  {
+  constructor(string tokenURI) public {
+    ERC20WithMetadata.initialize(tokenURI);
   }
 }

contracts/mocks/ERC721FullMock.sol

@@ -2,19 +2,24 @@ pragma solidity ^0.4.24;
 
 import "../token/ERC721/ERC721Full.sol";
 import "../token/ERC721/ERC721Mintable.sol";
+import "../token/ERC721/ERC721MetadataMintable.sol";
 import "../token/ERC721/ERC721Burnable.sol";
 
 
 /**
- * @title ERC721Mock
+ * @title ERC721FullMock
  * This mock just provides a public mint and burn functions for testing purposes,
  * and a public setter for metadata URI
  */
-contract ERC721FullMock is ERC721Full, ERC721Mintable, ERC721Burnable {
+contract ERC721FullMock is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
   constructor(string name, string symbol) public
-    ERC721Mintable()
-    ERC721Full(name, symbol)
-  {}
+  {
+    ERC721.initialize();
+    ERC721Metadata.initialize(name, symbol);
+    ERC721Enumerable.initialize();
+    ERC721Mintable.initialize(msg.sender);
+    ERC721MetadataMintable.initialize(msg.sender);
+  }
 
   function exists(uint256 tokenId) public view returns (bool) {
     return _exists(tokenId);

contracts/mocks/ERC721MintableBurnableImpl.sol

@@ -2,6 +2,7 @@ pragma solidity ^0.4.24;
 
 import "../token/ERC721/ERC721Full.sol";
 import "../token/ERC721/ERC721Mintable.sol";
+import "../token/ERC721/ERC721MetadataMintable.sol";
 import "../token/ERC721/ERC721Burnable.sol";
 
 
@@ -9,12 +10,15 @@ import "../token/ERC721/ERC721Burnable.sol";
  * @title ERC721MintableBurnableImpl
  */
 contract ERC721MintableBurnableImpl
-  is ERC721Full, ERC721Mintable, ERC721Burnable {
+  is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
 
   constructor()
-    ERC721Mintable()
-    ERC721Full("Test", "TEST")
     public
   {
+    ERC721.initialize();
+    ERC721Metadata.initialize("Test", "TEST");
+    ERC721Enumerable.initialize();
+    ERC721Mintable.initialize(msg.sender);
+    ERC721MetadataMintable.initialize(msg.sender);
   }
 }

contracts/mocks/ERC721Mock.sol

@@ -8,6 +8,10 @@ import "../token/ERC721/ERC721.sol";
  * This mock just provides a public mint and burn functions for testing purposes
  */
 contract ERC721Mock is ERC721 {
+  constructor() public {
+    ERC721.initialize();
+  }
+
   function mint(address to, uint256 tokenId) public {
     _mint(to, tokenId);
   }

contracts/mocks/ERC721PausableMock.sol

@@ -9,6 +9,11 @@ import "./PauserRoleMock.sol";
  * This mock just provides a public mint, burn and exists functions for testing purposes
  */
 contract ERC721PausableMock is ERC721Pausable, PauserRoleMock {
+  constructor() {
+    ERC721.initialize();
+    ERC721Pausable.initialize(msg.sender);
+  }
+
   function mint(address to, uint256 tokenId) public {
     super._mint(to, tokenId);
   }

contracts/mocks/EscrowMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.4.24;
+
+import "../payment/Escrow.sol";
+
+contract EscrowMock is Escrow {
+  constructor() public {
+    Escrow.initialize(msg.sender);
+  }
+}

contracts/mocks/FinalizableCrowdsaleImpl.sol

@@ -14,9 +14,9 @@ contract FinalizableCrowdsaleImpl is FinalizableCrowdsale {
     IERC20 token
   )
     public
-    Crowdsale(rate, wallet, token)
-    TimedCrowdsale(openingTime, closingTime)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    TimedCrowdsale.initialize(openingTime, closingTime);
   }
 
 }

contracts/mocks/IncreasingPriceCrowdsaleImpl.sol

@@ -15,10 +15,10 @@ contract IncreasingPriceCrowdsaleImpl is IncreasingPriceCrowdsale {
     uint256 finalRate
   )
     public
-    Crowdsale(initialRate, wallet, token)
-    TimedCrowdsale(openingTime, closingTime)
-    IncreasingPriceCrowdsale(initialRate, finalRate)
   {
+    Crowdsale.initialize(initialRate, wallet, token);
+    TimedCrowdsale.initialize(openingTime, closingTime);
+    IncreasingPriceCrowdsale.initialize(initialRate, finalRate);
   }
 
 }

contracts/mocks/IndividuallyCappedCrowdsaleImpl.sol

@@ -6,7 +6,7 @@ import "./CapperRoleMock.sol";
 
 
 contract IndividuallyCappedCrowdsaleImpl
-  is IndividuallyCappedCrowdsale, CapperRoleMock {
+  is Crowdsale, IndividuallyCappedCrowdsale, CapperRoleMock {
 
   constructor(
     uint256 rate,
@@ -14,7 +14,8 @@ contract IndividuallyCappedCrowdsaleImpl
     IERC20 token
   )
     public
-    Crowdsale(rate, wallet, token)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    IndividuallyCappedCrowdsale.initialize(msg.sender);
   }
 }

contracts/mocks/InsecureInvariantTargetBounty.sol

@@ -1,20 +0,0 @@
-pragma solidity ^0.4.24;
-
-// When this line is split, truffle parsing fails.
-// See: https://github.com/ethereum/solidity/issues/4871
-// solium-disable-next-line max-len
-import {BreakInvariantBounty, Target} from "../../contracts/bounties/BreakInvariantBounty.sol";
-
-
-contract InsecureInvariantTargetMock is Target {
-  function checkInvariant() public returns(bool) {
-    return false;
-  }
-}
-
-
-contract InsecureInvariantTargetBounty is BreakInvariantBounty {
-  function _deployContract() internal returns (address) {
-    return new InsecureInvariantTargetMock();
-  }
-}

contracts/mocks/MathMock.sol

@@ -1,7 +1,7 @@
 pragma solidity ^0.4.24;
 
 
-import "../../contracts/math/Math.sol";
+import "../math/Math.sol";
 
 
 contract MathMock {

contracts/mocks/MintedCrowdsaleImpl.sol

@@ -12,8 +12,8 @@ contract MintedCrowdsaleImpl is MintedCrowdsale {
     ERC20Mintable token
   )
     public
-    Crowdsale(rate, wallet, token)
   {
+    Crowdsale.initialize(rate, wallet, token);
   }
 
 }

contracts/mocks/MinterRoleMock.sol

@@ -4,6 +4,10 @@ import "../access/roles/MinterRole.sol";
 
 
 contract MinterRoleMock is MinterRole {
+  constructor() public {
+    MinterRole.initialize(msg.sender);
+  }
+
   function removeMinter(address account) public {
     _removeMinter(account);
   }

contracts/mocks/OwnableMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.4.24;
+
+import { Ownable } from "../ownership/Ownable.sol";
+
+contract OwnableMock is Ownable {
+  constructor() {
+    Ownable.initialize(msg.sender);
+  }
+}

contracts/mocks/PausableMock.sol

@@ -1,6 +1,5 @@
 pragma solidity ^0.4.24;
 
-
 import "../lifecycle/Pausable.sol";
 import "./PauserRoleMock.sol";
 
@@ -11,6 +10,8 @@ contract PausableMock is Pausable, PauserRoleMock {
   uint256 public count;
 
   constructor() public {
+    Pausable.initialize(msg.sender);
+
     drasticMeasureTaken = false;
     count = 0;
   }

contracts/mocks/PauserRoleMock.sol

@@ -4,6 +4,10 @@ import "../access/roles/PauserRole.sol";
 
 
 contract PauserRoleMock is PauserRole {
+  constructor() public {
+    PauserRole.initialize(msg.sender);
+  }
+
   function removePauser(address account) public {
     _removePauser(account);
   }

contracts/mocks/PostDeliveryCrowdsaleImpl.sol

@@ -14,9 +14,9 @@ contract PostDeliveryCrowdsaleImpl is PostDeliveryCrowdsale {
     IERC20 token
   )
     public
-    TimedCrowdsale(openingTime, closingTime)
-    Crowdsale(rate, wallet, token)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    TimedCrowdsale.initialize(openingTime, closingTime);
   }
 
 }

contracts/mocks/PullPaymentMock.sol

@@ -7,7 +7,9 @@ import "../payment/PullPayment.sol";
 // mock class using PullPayment
 contract PullPaymentMock is PullPayment {
 
-  constructor() public payable { }
+  constructor() public payable {
+    PullPayment.initialize();
+  }
 
   // test helper function to call asyncTransfer
   function callTransfer(address dest, uint256 amount) public {

contracts/mocks/ReentrancyMock.sol

@@ -9,6 +9,7 @@ contract ReentrancyMock is ReentrancyGuard {
   uint256 public counter;
 
   constructor() public {
+    ReentrancyGuard.initialize();
     counter = 0;
   }
 

contracts/mocks/RefundEscrowMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.4.24;
+
+import "../payment/RefundEscrow.sol";
+
+contract RefundEscrowMock is RefundEscrow {
+  constructor(address beneficiary) public {
+    RefundEscrow.initialize(beneficiary, msg.sender);
+  }
+}

contracts/mocks/RefundableCrowdsaleImpl.sol

@@ -4,7 +4,7 @@ import "../token/ERC20/ERC20Mintable.sol";
 import "../crowdsale/distribution/RefundableCrowdsale.sol";
 
 
-contract RefundableCrowdsaleImpl is RefundableCrowdsale {
+contract RefundableCrowdsaleImpl is Crowdsale, TimedCrowdsale, RefundableCrowdsale {
 
   constructor (
     uint256 openingTime,
@@ -15,10 +15,10 @@ contract RefundableCrowdsaleImpl is RefundableCrowdsale {
     uint256 goal
   )
     public
-    Crowdsale(rate, wallet, token)
-    TimedCrowdsale(openingTime, closingTime)
-    RefundableCrowdsale(goal)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    TimedCrowdsale.initialize(openingTime, closingTime);
+    RefundableCrowdsale.initialize(goal);
   }
 
 }

contracts/mocks/SampleCrowdsaleMock.sol

@@ -0,0 +1,26 @@
+pragma solidity ^0.4.24;
+
+import "../examples/SampleCrowdsale.sol";
+
+
+contract SampleCrowdsaleTokenMock is SampleCrowdsaleToken {
+  constructor() public {
+    SampleCrowdsaleToken.initialize(msg.sender);
+  }
+}
+
+contract SampleCrowdsaleMock is SampleCrowdsale {
+  constructor(
+    uint256 openingTime,
+    uint256 closingTime,
+    uint256 rate,
+    address wallet,
+    uint256 cap,
+    ERC20Mintable token,
+    uint256 goal
+  )
+    public
+  {
+    SampleCrowdsale.initialize(openingTime, closingTime, rate, wallet, cap, token, goal);
+  }
+}

contracts/mocks/SecondaryMock.sol

@@ -4,6 +4,10 @@ import "../ownership/Secondary.sol";
 
 
 contract SecondaryMock is Secondary {
+  constructor() public {
+    Secondary.initialize(msg.sender);
+  }
+
   function onlyPrimaryMock() public view onlyPrimary {
   }
 }

contracts/mocks/SecureInvariantTargetBounty.sol

@@ -1,20 +0,0 @@
-pragma solidity ^0.4.24;
-
-// When this line is split, truffle parsing fails.
-// See: https://github.com/ethereum/solidity/issues/4871
-// solium-disable-next-line max-len
-import {BreakInvariantBounty, Target} from "../../contracts/bounties/BreakInvariantBounty.sol";
-
-
-contract SecureInvariantTargetMock is Target {
-  function checkInvariant() public returns(bool) {
-    return true;
-  }
-}
-
-
-contract SecureInvariantTargetBounty is BreakInvariantBounty {
-  function _deployContract() internal returns (address) {
-    return new SecureInvariantTargetMock();
-  }
-}

contracts/mocks/SignatureBouncerMock.sol

@@ -5,6 +5,10 @@ import "./SignerRoleMock.sol";
 
 
 contract SignatureBouncerMock is SignatureBouncer, SignerRoleMock {
+  constructor() public {
+    SignatureBouncer.initialize(msg.sender);
+  }
+
   function checkValidSignature(address account, bytes signature)
     public
     view
@@ -64,4 +68,11 @@ contract SignatureBouncerMock is SignatureBouncer, SignerRoleMock {
   {
 
   }
+
+  function tooShortMsgData()
+    public
+    onlyValidSignatureAndData("")
+    view
+  {
+  }
 }

contracts/mocks/SignerRoleMock.sol

@@ -4,6 +4,10 @@ import "../access/roles/SignerRole.sol";
 
 
 contract SignerRoleMock is SignerRole {
+  constructor() public {
+    SignerRole.initialize(msg.sender);
+  }
+
   function removeSigner(address account) public {
     _removeSigner(account);
   }

contracts/mocks/SimpleTokenMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.4.24;
+
+import "../examples/SimpleToken.sol";
+
+contract SimpleTokenMock is SimpleToken {
+  constructor() public {
+    SimpleToken.initialize(msg.sender);
+  }
+}

contracts/mocks/SplitPaymentMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.4.24;
+
+import "../payment/SplitPayment.sol";
+
+contract SplitPaymentMock is SplitPayment {
+  constructor(address[] payees, uint256[] shares) public {
+    SplitPayment.initialize(payees, shares);
+  }
+}

contracts/mocks/TimedCrowdsaleImpl.sol

@@ -14,9 +14,9 @@ contract TimedCrowdsaleImpl is TimedCrowdsale {
     IERC20 token
   )
     public
-    Crowdsale(rate, wallet, token)
-    TimedCrowdsale(openingTime, closingTime)
   {
+    Crowdsale.initialize(rate, wallet, token);
+    TimedCrowdsale.initialize(openingTime, closingTime);
   }
 
 }

contracts/mocks/TokenTimelockMock.sol

@@ -0,0 +1,13 @@
+pragma solidity ^0.4.24;
+
+import "../token/ERC20/TokenTimelock.sol";
+
+contract TokenTimelockMock is TokenTimelock {
+  constructor(
+    IERC20 token,
+    address beneficiary,
+    uint256 releaseTime
+  ) public {
+    TokenTimelock.initialize(token, beneficiary, releaseTime);
+  }
+}

contracts/mocks/TokenVestingMock.sol

@@ -0,0 +1,22 @@
+pragma solidity ^0.4.24;
+
+import "../drafts/TokenVesting.sol";
+
+contract TokenVestingMock is TokenVesting {
+  constructor(
+    address beneficiary,
+    uint256 start,
+    uint256 cliffDuration,
+    uint256 duration,
+    bool revocable
+  ) public {
+    TokenVesting.initialize(
+      beneficiary,
+      start,
+      cliffDuration,
+      duration,
+      revocable,
+      msg.sender
+    );
+  }
+}

contracts/ownership/Ownable.sol

@@ -1,12 +1,13 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 
 /**
  * @title Ownable
  * @dev The Ownable contract has an owner address, and provides basic authorization control
  * functions, this simplifies the implementation of "user permissions".
  */
-contract Ownable {
+contract Ownable is Initializable {
   address private _owner;
 
 
@@ -21,8 +22,8 @@ contract Ownable {
    * @dev The Ownable constructor sets the original `owner` of the contract to the sender
    * account.
    */
-  constructor() public {
-    _owner = msg.sender;
+  function initialize(address sender) public initializer {
+    _owner = sender;
   }
 
   /**
@@ -75,4 +76,6 @@ contract Ownable {
     emit OwnershipTransferred(_owner, newOwner);
     _owner = newOwner;
   }
+
+  uint256[50] private ______gap;
 }

contracts/ownership/Secondary.sol

@@ -1,18 +1,19 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 
 /**
  * @title Secondary
  * @dev A Secondary contract can only be used by its primary account (the one that created it)
  */
-contract Secondary {
+contract Secondary is Initializable {
   address private _primary;
 
   /**
    * @dev Sets the primary account to the one that is creating the Secondary contract.
    */
-  constructor() public {
-    _primary = msg.sender;
+  function initialize(address sender) public initializer {
+    _primary = sender;
   }
 
   /**
@@ -32,4 +33,6 @@ contract Secondary {
 
     _primary = recipient;
   }
+
+  uint256[50] private ______gap;
 }

contracts/payment/ConditionalEscrow.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./Escrow.sol";
 
 
@@ -7,7 +8,11 @@ import "./Escrow.sol";
  * @title ConditionalEscrow
  * @dev Base abstract escrow to only allow withdrawal if a condition is met.
  */
-contract ConditionalEscrow is Escrow {
+contract ConditionalEscrow is Initializable, Escrow {
+  function initialize(address sender) public initializer {
+    Escrow.initialize(sender);
+  }
+
   /**
   * @dev Returns whether an address is allowed to withdraw their funds. To be
   * implemented by derived contracts.
@@ -19,4 +24,6 @@ contract ConditionalEscrow is Escrow {
     require(withdrawalAllowed(payee));
     super.withdraw(payee);
   }
+
+  uint256[50] private ______gap;
 }

contracts/payment/Escrow.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../math/SafeMath.sol";
 import "../ownership/Secondary.sol";
 
@@ -11,7 +12,7 @@ import "../ownership/Secondary.sol";
  * should be its primary, and provide public methods redirecting to the escrow's
  * deposit and withdraw.
  */
-contract Escrow is Secondary {
+contract Escrow is Initializable, Secondary {
   using SafeMath for uint256;
 
   event Deposited(address indexed payee, uint256 weiAmount);
@@ -19,6 +20,10 @@ contract Escrow is Secondary {
 
   mapping(address => uint256) private _deposits;
 
+  function initialize(address sender) public initializer {
+    Secondary.initialize(sender);
+  }
+
   function depositsOf(address payee) public view returns (uint256) {
     return _deposits[payee];
   }
@@ -40,7 +45,6 @@ contract Escrow is Secondary {
   */
   function withdraw(address payee) public onlyPrimary {
     uint256 payment = _deposits[payee];
-    assert(address(this).balance >= payment);
 
     _deposits[payee] = 0;
 
@@ -48,4 +52,6 @@ contract Escrow is Secondary {
 
     emit Withdrawn(payee, payment);
   }
+
+  uint256[50] private ______gap;
 }

contracts/payment/PullPayment.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./Escrow.sol";
 
 
@@ -8,11 +9,15 @@ import "./Escrow.sol";
  * @dev Base contract supporting async send for pull payments. Inherit from this
  * contract and use _asyncTransfer instead of send or transfer.
  */
-contract PullPayment {
+contract PullPayment is Initializable {
   Escrow private _escrow;
 
-  constructor() public {
-    _escrow = new Escrow();
+  function initialize() public initializer {
+    // conditional added to make initializer idempotent in case of diamond inheritance
+    if (address(_escrow) == address(0)) {
+      _escrow = new Escrow();
+      _escrow.initialize(address(this));
+    }
   }
 
   /**
@@ -39,4 +44,6 @@ contract PullPayment {
   function _asyncTransfer(address dest, uint256 amount) internal {
     _escrow.deposit.value(amount)(dest);
   }
+
+  uint256[50] private ______gap;
 }

contracts/payment/RefundEscrow.sol

@@ -1,7 +1,7 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ConditionalEscrow.sol";
-import "../ownership/Secondary.sol";
 
 
 /**
@@ -10,7 +10,7 @@ import "../ownership/Secondary.sol";
  * The primary account may close the deposit period, and allow for either withdrawal
  * by the beneficiary, or refunds to the depositors.
  */
-contract RefundEscrow is Secondary, ConditionalEscrow {
+contract RefundEscrow is Initializable, ConditionalEscrow {
   enum State { Active, Refunding, Closed }
 
   event Closed();
@@ -23,7 +23,9 @@ contract RefundEscrow is Secondary, ConditionalEscrow {
    * @dev Constructor.
    * @param beneficiary The beneficiary of the deposits.
    */
-  constructor(address beneficiary) public {
+  function initialize(address beneficiary, address sender) public initializer {
+    ConditionalEscrow.initialize(sender);
+
     require(beneficiary != address(0));
     _beneficiary = beneficiary;
     _state = State.Active;
@@ -85,4 +87,6 @@ contract RefundEscrow is Secondary, ConditionalEscrow {
   function withdrawalAllowed(address payee) public view returns (bool) {
     return _state == State.Refunding;
   }
+
+  uint256[50] private ______gap;
 }

contracts/payment/SplitPayment.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../math/SafeMath.sol";
 
 
@@ -8,11 +9,11 @@ import "../math/SafeMath.sol";
  * @dev This contract can be used when payments need to be received by a group
  * of people and split proportionately to some number of shares they own.
  */
-contract SplitPayment {
+contract SplitPayment is Initializable {
   using SafeMath for uint256;
 
-  uint256 private _totalShares = 0;
-  uint256 private _totalReleased = 0;
+  uint256 private _totalShares;
+  uint256 private _totalReleased;
 
   mapping(address => uint256) private _shares;
   mapping(address => uint256) private _released;
@@ -21,7 +22,7 @@ contract SplitPayment {
   /**
    * @dev Constructor
    */
-  constructor(address[] payees, uint256[] shares) public payable {
+  function initialize(address[] payees, uint256[] shares) public payable initializer {
     require(payees.length == shares.length);
     require(payees.length > 0);
 
@@ -85,7 +86,6 @@ contract SplitPayment {
     );
 
     require(payment != 0);
-    assert(address(this).balance >= payment);
 
     _released[account] = _released[account].add(payment);
     _totalReleased = _totalReleased.add(payment);
@@ -107,4 +107,6 @@ contract SplitPayment {
     _shares[account] = shares_;
     _totalShares = _totalShares.add(shares_);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/ERC20.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./IERC20.sol";
 import "../../math/SafeMath.sol";
 
@@ -11,7 +12,7 @@ import "../../math/SafeMath.sol";
  * https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md
  * Originally based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
  */
-contract ERC20 is IERC20 {
+contract ERC20 is Initializable, IERC20 {
   using SafeMath for uint256;
 
   mapping (address => uint256) private _balances;
@@ -59,12 +60,7 @@ contract ERC20 is IERC20 {
   * @param value The amount to be transferred.
   */
   function transfer(address to, uint256 value) public returns (bool) {
-    require(value <= _balances[msg.sender]);
-    require(to != address(0));
-
-    _balances[msg.sender] = _balances[msg.sender].sub(value);
-    _balances[to] = _balances[to].add(value);
-    emit Transfer(msg.sender, to, value);
+    _transfer(msg.sender, to, value);
     return true;
   }
 
@@ -99,14 +95,10 @@ contract ERC20 is IERC20 {
     public
     returns (bool)
   {
-    require(value <= _balances[from]);
     require(value <= _allowed[from][msg.sender]);
-    require(to != address(0));
 
-    _balances[from] = _balances[from].sub(value);
-    _balances[to] = _balances[to].add(value);
     _allowed[from][msg.sender] = _allowed[from][msg.sender].sub(value);
-    emit Transfer(from, to, value);
+    _transfer(from, to, value);
     return true;
   }
 
@@ -158,6 +150,21 @@ contract ERC20 is IERC20 {
     return true;
   }
 
+  /**
+  * @dev Transfer token for a specified addresses
+  * @param from The address to transfer from.
+  * @param to The address to transfer to.
+  * @param value The amount to be transferred.
+  */
+  function _transfer(address from, address to, uint256 value) internal {
+    require(value <= _balances[from]);
+    require(to != address(0));
+
+    _balances[from] = _balances[from].sub(value);
+    _balances[to] = _balances[to].add(value);
+    emit Transfer(from, to, value);
+  }
+
   /**
    * @dev Internal function that mints an amount of the token and assigns it to
    * an account. This encapsulates the modification of balances such that the
@@ -203,4 +210,6 @@ contract ERC20 is IERC20 {
       amount);
     _burn(account, amount);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/ERC20Burnable.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC20.sol";
 
 
@@ -7,7 +8,7 @@ import "./ERC20.sol";
  * @title Burnable Token
  * @dev Token that can be irreversibly burned (destroyed).
  */
-contract ERC20Burnable is ERC20 {
+contract ERC20Burnable is Initializable, ERC20 {
 
   /**
    * @dev Burns a specific amount of tokens.
@@ -26,11 +27,5 @@ contract ERC20Burnable is ERC20 {
     _burnFrom(from, value);
   }
 
-  /**
-   * @dev Overrides ERC20._burn in order for burn and burnFrom to emit
-   * an additional Burn event.
-   */
-  function _burn(address who, uint256 value) internal {
-    super._burn(who, value);
-  }
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/ERC20Capped.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC20Mintable.sol";
 
 
@@ -7,13 +8,16 @@ import "./ERC20Mintable.sol";
  * @title Capped token
  * @dev Mintable token with a token cap.
  */
-contract ERC20Capped is ERC20Mintable {
+contract ERC20Capped is Initializable, ERC20Mintable {
 
   uint256 private _cap;
 
-  constructor(uint256 cap)
+  function initialize(uint256 cap, address sender)
     public
+    initializer
   {
+    ERC20Mintable.initialize(sender);
+
     require(cap > 0);
     _cap = cap;
   }
@@ -43,4 +47,6 @@ contract ERC20Capped is ERC20Mintable {
     return super.mint(to, amount);
   }
 
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/ERC20Detailed.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./IERC20.sol";
 
 
@@ -9,12 +10,12 @@ import "./IERC20.sol";
  * All the operations are done using the smallest and indivisible token unit,
  * just as on Ethereum all the operations are done in wei.
  */
-contract ERC20Detailed is IERC20 {
+contract ERC20Detailed is Initializable, IERC20 {
   string private _name;
   string private _symbol;
   uint8 private _decimals;
 
-  constructor(string name, string symbol, uint8 decimals) public {
+  function initialize(string name, string symbol, uint8 decimals) public initializer {
     _name = name;
     _symbol = symbol;
     _decimals = decimals;
@@ -40,4 +41,6 @@ contract ERC20Detailed is IERC20 {
   function decimals() public view returns(uint8) {
     return _decimals;
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/ERC20Mintable.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC20.sol";
 import "../../access/roles/MinterRole.sol";
 
@@ -8,21 +9,9 @@ import "../../access/roles/MinterRole.sol";
  * @title ERC20Mintable
  * @dev ERC20 minting logic
  */
-contract ERC20Mintable is ERC20, MinterRole {
-  event MintingFinished();
-
-  bool private _mintingFinished = false;
-
-  modifier onlyBeforeMintingFinished() {
-    require(!_mintingFinished);
-    _;
-  }
-
-  /**
-   * @return true if the minting is finished.
-   */
-  function mintingFinished() public view returns(bool) {
-    return _mintingFinished;
+contract ERC20Mintable is Initializable, ERC20, MinterRole {
+  function initialize(address sender) public initializer {
+    MinterRole.initialize(sender);
   }
 
   /**
@@ -37,25 +26,11 @@ contract ERC20Mintable is ERC20, MinterRole {
   )
     public
     onlyMinter
-    onlyBeforeMintingFinished
     returns (bool)
   {
     _mint(to, amount);
     return true;
   }
 
-  /**
-   * @dev Function to stop minting new tokens.
-   * @return True if the operation was successful.
-   */
-  function finishMinting()
-    public
-    onlyMinter
-    onlyBeforeMintingFinished
-    returns (bool)
-  {
-    _mintingFinished = true;
-    emit MintingFinished();
-    return true;
-  }
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/ERC20Pausable.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC20.sol";
 import "../../lifecycle/Pausable.sol";
 
@@ -8,7 +9,11 @@ import "../../lifecycle/Pausable.sol";
  * @title Pausable token
  * @dev ERC20 modified with pausable transfers.
  **/
-contract ERC20Pausable is ERC20, Pausable {
+contract ERC20Pausable is Initializable, ERC20, Pausable {
+
+  function initialize(address sender) public initializer {
+    Pausable.initialize(sender);
+  }
 
   function transfer(
     address to,
@@ -65,4 +70,6 @@ contract ERC20Pausable is ERC20, Pausable {
   {
     return super.decreaseAllowance(spender, subtractedValue);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC20/StandaloneERC20.sol

@@ -0,0 +1,65 @@
+pragma solidity ^0.4.24;
+
+import "zos-lib/contracts/Initializable.sol";
+import "./ERC20Detailed.sol";
+import "./ERC20Mintable.sol";
+import "./ERC20Pausable.sol";
+
+
+/**
+ * @title Standard ERC20 token, with minting and pause functionality.
+ *
+ */
+contract StandaloneERC20 is Initializable, ERC20Detailed, ERC20Mintable, ERC20Pausable {
+  function initialize(
+    string name, string symbol, uint8 decimals, uint256 initialSupply, address initialHolder,
+    address[] minters, address[] pausers
+  ) public initializer {
+    require(initialSupply > 0);
+
+    ERC20Detailed.initialize(name, symbol, decimals);
+
+    // Mint the initial supply
+    _mint(initialHolder, initialSupply);
+
+    // Initialize the minter and pauser roles, and renounce them
+    ERC20Mintable.initialize(address(this));
+    renounceMinter();
+
+    ERC20Pausable.initialize(address(this));
+    renouncePauser();
+
+    // Add the requested minters and pausers (this can be done after renouncing since
+    // these are the internal calls)
+    for (uint256 i = 0; i < minters.length; ++i) {
+      _addMinter(minters[i]);
+    }
+
+    for (i = 0; i < pausers.length; ++i) {
+      _addPauser(pausers[i]);
+    }
+  }
+
+  function initialize(
+    string name, string symbol, uint8 decimals, address[] minters, address[] pausers
+  ) public initializer {
+    ERC20Detailed.initialize(name, symbol, decimals);
+
+    // Initialize the minter and pauser roles, and renounce them
+    ERC20Mintable.initialize(address(this));
+    renounceMinter();
+
+    ERC20Pausable.initialize(address(this));
+    renouncePauser();
+
+    // Add the requested minters and pausers (this can be done after renouncing since
+    // these are the internal calls)
+    for (uint256 i = 0; i < minters.length; ++i) {
+      _addMinter(minters[i]);
+    }
+
+    for (i = 0; i < pausers.length; ++i) {
+      _addPauser(pausers[i]);
+    }
+  }
+}

contracts/token/ERC20/TokenTimelock.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./SafeERC20.sol";
 
 
@@ -8,7 +9,7 @@ import "./SafeERC20.sol";
  * @dev TokenTimelock is a token holder contract that will allow a
  * beneficiary to extract the tokens after a given release time
  */
-contract TokenTimelock {
+contract TokenTimelock is Initializable {
   using SafeERC20 for IERC20;
 
   // ERC20 basic token contract being held
@@ -20,12 +21,13 @@ contract TokenTimelock {
   // timestamp when token release is enabled
   uint256 private _releaseTime;
 
-  constructor(
+  function initialize(
     IERC20 token,
     address beneficiary,
     uint256 releaseTime
   )
     public
+    initializer
   {
     // solium-disable-next-line security/no-block-members
     require(releaseTime > block.timestamp);
@@ -67,4 +69,6 @@ contract TokenTimelock {
 
     _token.safeTransfer(_beneficiary, amount);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./IERC721.sol";
 import "./IERC721Receiver.sol";
 import "../../math/SafeMath.sol";
@@ -11,7 +12,7 @@ import "../../introspection/ERC165.sol";
  * @title ERC721 Non-Fungible Token Standard basic implementation
  * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
  */
-contract ERC721 is ERC165, IERC721 {
+contract ERC721 is Initializable, ERC165, IERC721 {
 
   using SafeMath for uint256;
   using Address for address;
@@ -46,13 +47,20 @@ contract ERC721 is ERC165, IERC721 {
    *   bytes4(keccak256('safeTransferFrom(address,address,uint256,bytes)'))
    */
 
-  constructor()
+  function initialize()
     public
+    initializer
   {
+    ERC165.initialize();
+
     // register the supported interfaces to conform to ERC721 via ERC165
     _registerInterface(_InterfaceId_ERC721);
   }
 
+  function _hasBeenInitialized() internal view returns (bool) {
+    return supportsInterface(_InterfaceId_ERC721);
+  }
+
   /**
    * @dev Gets the balance of the specified address
    * @param owner address to query the balance of
@@ -323,4 +331,6 @@ contract ERC721 is ERC165, IERC721 {
       msg.sender, from, tokenId, _data);
     return (retval == _ERC721_RECEIVED);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721Burnable.sol

@@ -1,13 +1,16 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC721.sol";
 
 
-contract ERC721Burnable is ERC721 {
+contract ERC721Burnable is Initializable, ERC721 {
   function burn(uint256 tokenId)
     public
   {
     require(_isApprovedOrOwner(msg.sender, tokenId));
     _burn(ownerOf(tokenId), tokenId);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721Enumerable.sol

@@ -1,11 +1,12 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./IERC721Enumerable.sol";
 import "./ERC721.sol";
 import "../../introspection/ERC165.sol";
 
 
-contract ERC721Enumerable is ERC165, ERC721, IERC721Enumerable {
+contract ERC721Enumerable is Initializable, ERC165, ERC721, IERC721Enumerable {
   // Mapping from owner to list of owned token IDs
   mapping(address => uint256[]) private _ownedTokens;
 
@@ -29,11 +30,17 @@ contract ERC721Enumerable is ERC165, ERC721, IERC721Enumerable {
   /**
    * @dev Constructor function
    */
-  constructor() public {
+  function initialize() public initializer {
+    require(ERC721._hasBeenInitialized());
+
     // register the supported interface to conform to ERC721 via ERC165
     _registerInterface(_InterfaceId_ERC721Enumerable);
   }
 
+  function _hasBeenInitialized() internal view returns (bool) {
+    return supportsInterface(_InterfaceId_ERC721Enumerable);
+  }
+
   /**
    * @dev Gets the token ID at a given index of the tokens list of the requested owner
    * @param owner address owning the tokens list to be accessed
@@ -143,4 +150,6 @@ contract ERC721Enumerable is ERC165, ERC721, IERC721Enumerable {
     _allTokensIndex[tokenId] = 0;
     _allTokensIndex[lastToken] = tokenIndex;
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721Full.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC721.sol";
 import "./ERC721Enumerable.sol";
 import "./ERC721Metadata.sol";
@@ -11,9 +12,6 @@ import "./ERC721Metadata.sol";
  * Moreover, it includes approve all functionality using operator terminology
  * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
  */
-contract ERC721Full is ERC721, ERC721Enumerable, ERC721Metadata {
-  constructor(string name, string symbol) ERC721Metadata(name, symbol)
-    public
-  {
-  }
+contract ERC721Full is Initializable, ERC721, ERC721Enumerable, ERC721Metadata {
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721Holder.sol

@@ -1,9 +1,10 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./IERC721Receiver.sol";
 
 
-contract ERC721Holder is IERC721Receiver {
+contract ERC721Holder is Initializable, IERC721Receiver {
   function onERC721Received(
     address,
     address,
@@ -15,4 +16,6 @@ contract ERC721Holder is IERC721Receiver {
   {
     return this.onERC721Received.selector;
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721Metadata.sol

@@ -1,11 +1,12 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC721.sol";
 import "./IERC721Metadata.sol";
 import "../../introspection/ERC165.sol";
 
 
-contract ERC721Metadata is ERC165, ERC721, IERC721Metadata {
+contract ERC721Metadata is Initializable, ERC165, ERC721, IERC721Metadata {
   // Token name
   string internal _name;
 
@@ -26,7 +27,9 @@ contract ERC721Metadata is ERC165, ERC721, IERC721Metadata {
   /**
    * @dev Constructor function
    */
-  constructor(string name, string symbol) public {
+  function initialize(string name, string symbol) public initializer {
+    require(ERC721._hasBeenInitialized());
+
     _name = name;
     _symbol = symbol;
 
@@ -34,6 +37,10 @@ contract ERC721Metadata is ERC165, ERC721, IERC721Metadata {
     _registerInterface(InterfaceId_ERC721Metadata);
   }
 
+  function _hasBeenInitialized() internal view returns (bool) {
+    return supportsInterface(InterfaceId_ERC721Metadata);
+  }
+
   /**
    * @dev Gets the token name
    * @return string representing the token name
@@ -85,4 +92,6 @@ contract ERC721Metadata is ERC165, ERC721, IERC721Metadata {
       delete _tokenURIs[tokenId];
     }
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721MetadataMintable.sol

@@ -0,0 +1,41 @@
+pragma solidity ^0.4.24;
+
+import "zos-lib/contracts/Initializable.sol";
+import "./ERC721Metadata.sol";
+import "../../access/roles/MinterRole.sol";
+
+
+/**
+ * @title ERC721MetadataMintable
+ * @dev ERC721 minting logic with metadata
+ */
+contract ERC721MetadataMintable is Initializable, ERC721, ERC721Metadata, MinterRole {
+  function initialize(address sender) public initializer {
+    require(ERC721._hasBeenInitialized());
+    require(ERC721Metadata._hasBeenInitialized());
+    MinterRole.initialize(sender);
+  }
+
+  /**
+   * @dev Function to mint tokens
+   * @param to The address that will receive the minted tokens.
+   * @param tokenId The token id to mint.
+   * @param tokenURI The token URI of the minted token.
+   * @return A boolean that indicates if the operation was successful.
+   */
+  function mintWithTokenURI(
+    address to,
+    uint256 tokenId,
+    string tokenURI
+  )
+    public
+    onlyMinter
+    returns (bool)
+  {
+    _mint(to, tokenId);
+    _setTokenURI(tokenId, tokenURI);
+    return true;
+  }
+
+  uint256[50] private ______gap;
+}

contracts/token/ERC721/ERC721Mintable.sol

@@ -1,6 +1,7 @@
 pragma solidity ^0.4.24;
 
-import "./ERC721Full.sol";
+import "zos-lib/contracts/Initializable.sol";
+import "./ERC721.sol";
 import "../../access/roles/MinterRole.sol";
 
 
@@ -8,21 +9,10 @@ import "../../access/roles/MinterRole.sol";
  * @title ERC721Mintable
  * @dev ERC721 minting logic
  */
-contract ERC721Mintable is ERC721Full, MinterRole {
-  event MintingFinished();
-
-  bool private _mintingFinished = false;
-
-  modifier onlyBeforeMintingFinished() {
-    require(!_mintingFinished);
-    _;
-  }
-
-  /**
-   * @return true if the minting is finished.
-   */
-  function mintingFinished() public view returns(bool) {
-    return _mintingFinished;
+contract ERC721Mintable is Initializable, ERC721, MinterRole {
+  function initialize(address sender) public initializer {
+    require(ERC721._hasBeenInitialized());
+    MinterRole.initialize(sender);
   }
 
   /**
@@ -37,40 +27,11 @@ contract ERC721Mintable is ERC721Full, MinterRole {
   )
     public
     onlyMinter
-    onlyBeforeMintingFinished
     returns (bool)
   {
     _mint(to, tokenId);
     return true;
   }
 
-  function mintWithTokenURI(
-    address to,
-    uint256 tokenId,
-    string tokenURI
-  )
-    public
-    onlyMinter
-    onlyBeforeMintingFinished
-    returns (bool)
-  {
-    mint(to, tokenId);
-    _setTokenURI(tokenId, tokenURI);
-    return true;
-  }
-
-  /**
-   * @dev Function to stop minting new tokens.
-   * @return True if the operation was successful.
-   */
-  function finishMinting()
-    public
-    onlyMinter
-    onlyBeforeMintingFinished
-    returns (bool)
-  {
-    _mintingFinished = true;
-    emit MintingFinished();
-    return true;
-  }
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/ERC721Pausable.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "./ERC721.sol";
 import "../../lifecycle/Pausable.sol";
 
@@ -8,7 +9,12 @@ import "../../lifecycle/Pausable.sol";
  * @title ERC721 Non-Fungible Pausable token
  * @dev ERC721 modified with pausable transfers.
  **/
-contract ERC721Pausable is ERC721, Pausable {
+contract ERC721Pausable is Initializable, ERC721, Pausable {
+  function initialize(address sender) public initializer {
+    require(ERC721._hasBeenInitialized());
+    Pausable.initialize(sender);
+  }
+
   function approve(
     address to,
     uint256 tokenId
@@ -39,4 +45,6 @@ contract ERC721Pausable is ERC721, Pausable {
   {
     super.transferFrom(from, to, tokenId);
   }
+
+  uint256[50] private ______gap;
 }

contracts/token/ERC721/IERC721.sol

@@ -1,5 +1,6 @@
 pragma solidity ^0.4.24;
 
+import "zos-lib/contracts/Initializable.sol";
 import "../../introspection/IERC165.sol";
 
 
@@ -7,7 +8,7 @@ import "../../introspection/IERC165.sol";
  * @title ERC721 Non-Fungible Token Standard basic interface
  * @dev see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-721.md
  */
-contract IERC721 is IERC165 {
+contract IERC721 is Initializable, IERC165 {
 
   event Transfer(
     address indexed from,