I am trying to deploy the Uniswap v2 Factory contract on my ganache test network. I have compiled these contracts with my own compiler. But everything I attempt to deploy the Factory, I receive this error c: VM Exception while processing transaction: out of gas.

When I check the compiledFactory.evm.gasEstimates.creation here is what I receive : { codeDepositCost: '2155800', executionCost: 'infinite', totalCost: 'infinite' }.

I have heared problems about deploying the Uni v2 Router contract, but not the factory ? I tried to comment the allPairLength function in the UniswapV2Factory contract, but the result is the same.

Here is the UniswapV2Factory contract that I deploy (pulled from the Uniswap github, so it should be the same):

pragma solidity =0.5.16;

import './interfaces/IUniswapV2Factory.sol';
import './UniswapV2Pair.sol';

contract UniswapV2Factory is IUniswapV2Factory {
    address public feeTo;
    address public feeToSetter;

    mapping(address => mapping(address => address)) public getPair;
    address[] public allPairs;

    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    constructor(address _feeToSetter) public {
        feeToSetter = _feeToSetter;

    function allPairsLength() external view returns (uint) {
        return allPairs.length;

    function createPair(address tokenA, address tokenB) external returns (address pair) {
        require(tokenA != tokenB, 'UniswapV2: IDENTICAL_ADDRESSES');
        (address token0, address token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'UniswapV2: ZERO_ADDRESS');
        require(getPair[token0][token1] == address(0), 'UniswapV2: PAIR_EXISTS'); // single check is sufficient
        bytes memory bytecode = type(UniswapV2Pair).creationCode;
        bytes32 salt = keccak256(abi.encodePacked(token0, token1));
        assembly {
            pair := create2(0, add(bytecode, 32), mload(bytecode), salt)
        IUniswapV2Pair(pair).initialize(token0, token1);
        getPair[token0][token1] = pair;
        getPair[token1][token0] = pair; // populate mapping in the reverse direction
        emit PairCreated(token0, token1, pair, allPairs.length);

    function setFeeTo(address _feeTo) external {
        require(msg.sender == feeToSetter, 'UniswapV2: FORBIDDEN');
        feeTo = _feeTo;

    function setFeeToSetter(address _feeToSetter) external {
        require(msg.sender == feeToSetter, 'UniswapV2: FORBIDDEN');
        feeToSetter = _feeToSetter;

here is my test file :

const assert = require("assert");
const ganache = require("ganache-cli");
const Web3 = require("web3");
const web3 = new Web3(ganache.provider());

const compiledFactory = require("../ethereum/contracts/core/build/UniswapV2Factory.json");
const compiledERC20 = require("../ethereum/contracts/core/build/ERC20.json");

let accounts;
let erc20Contract;
let factory ;
let token1;
let token2;
let token1Address;
let token2Address;
let poolAddress;

beforeEach(async function() {
    accounts = await web3.eth.getAccounts();

    // console.log(compiledFactory.evm.gasEstimates.creation);
    // console.log(compiledFactory);

    token1 = await new web3.eth.Contract(compiledERC20.abi).deploy({ data: compiledERC20.evm.bytecode.object, arguments: [100] }).send({ from: accounts[0], gas: "1000000" });
    token2 = await new web3.eth.Contract(compiledERC20.abi).deploy({ data: compiledERC20.evm.bytecode.object, arguments: [100] }).send({ from: accounts[0], gas: "1000000" });

    factory = await new web3.eth.Contract(compiledFactory.abi).deploy({ data: compiledFactory.evm.bytecode.object, arguments: [accounts[0]] }).send({ from: accounts[0], gas: "1000000" });

    token1Address = token1.options.address;
    token2Address = token2.options.address;

    // poolAddress = factory.methods.createPair(token1Address, token2Address);

describe("Tokens", function() {
    it("deploy two tokens", () => {

describe("Factory", function() {
    it("deploy the factory", () => {
    it("deploy a liquidity pool", () => {

here is my full repo (https://github.com/d-s-i/uniswap-fork) if you want to see the whole code (all contracts, compiled contract, and compile script are in the ethereum/contracts/core folder).

Thanks to anyone for considering helping

  • You provide only 1 000 000 of gas. Usually deployment of a contract costs more gas. Jul 25 '21 at 15:49
  • if you are short on money to deploy, you can call functions in other similar contracts, but it will cost you more gas at runtime since external call costs more gas
    – Nulik
    Jul 25 '21 at 15:53
  • deploy on Sunday/Saturday morning NY time and you will get lowest gas price
    – Nulik
    Jul 25 '21 at 15:53
  • Yes I see but I tried upgrading to "100000000000" for example and I receive this error : n: Exceeds block gas limit. Side note, this is only ganache so it's not real money ... I could spend any gas amount I want. Note that the gasEstimates function return "infinity", I don't know why
    – Cizia
    Jul 25 '21 at 16:04
  • 1
    Oh it worked. For whatever reason I didn't think a too high gas in a transaction was possible, and that the error returned a general error for the whole block gas spent. Thank you so much Prorok ...
    – Cizia
    Jul 25 '21 at 16:14

Iv run into similar issues.

In your truffle configuration file, make sure you enable optimization i. The compiler settings. Setting to 200 is fine. Essentially the fact that the contract code isn't optimized, you end up running out of gas

Hope this helps,


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