Contacts

• Discord: 0xFar5eer#6504 / AnotherDev#1180
• Telegram @instarogar / @Someone_Nevv

Smart Contracts Description

The contract was built completely from scratch following uniswap v2 whitepaper. Code was optimized for swaps. The following results were achieved:

• swapping XDC --> CUPEX, costs 64,018 gas https://apothem.blocksscan.io/tx/0xf6bddf342fc8e606acfe6e5d3989b35db5f1dd0c31be77465ecc9f2dc1943fd3
• swapping CUPEX --> XDC, costs 70,803 gas https://apothem.blocksscan.io/tx/0x0ec27592a3665a1fbf5cff4013b7200dba92ab126e530f8421d5ddfa7ddab483
• swapping USDC --> DAI, costs 106,968 gas https://apothem.blocksscan.io/tx/0x5d8e3fa5e36a4d3c222727bb71898ff006166b4599f7c6edf3f03bf3a982b371

Comparing to uniswap v2 swaps which takes 110,000 per swap. Cupcake DEX costs 3-41% cheaper. The optimization is not final, gas usage can be reduced even further but for the simplicity of the contract some of the optimizations were omitted such as:

• using clone factory for new pairs which allows us to remove several fields from storage (gives additional 20-30% gas usage decrease)
• tightly fitting storage space (gives additional 1-5% gas usage decrease)
• instead of ERC20 token for Liquidity Providing, DEX uses ERC1155 tokens

The features of this DEX:

• native tokens XDC aren't converted to wrapped version WXDC
• all tokens are stored on the single main contract address which means no new pair contracts are created
• there is no router contract needed as everything fits in a single contract
• all ERC20 or native tokens must be paired with CUPEX token only which allows us to swap Any Token1 <--> Any Token2 using CUPEX Token in between (Token1 --> CUPEX --> Token2). This is hidden inside the contract logics for user's convenience.
• simple and convenient swapping interface functions for developers
• single DEX contract hosts ERC1155 Liquidity Provider tokens
• code is very well commented and should be simple to understand
• swap fee is static 0.15% per each swap
• MIT license allows anyone to continue development

Staking option:

• DEX supports simple staking operations such as createStake and unStake
• simple algorithm applied: 10% daily inflation for CUPEX tokens
• on createStake tokens are burned
• on unStake tokens are minted plus interest

Limitations:

• for testing purposes all Approvals were disabled in the ERC20 token contracts, in production it must be added back
• staking is calling unprotected mint/burn functions, in production whitelist protection must be added

XDC Mainnet contracts deployed

XDC Mainnet:

• CupexDEX: 0xDEFf68298424f4e49aCc94C17446f075E4c78850
• CupexStaking: 0x1F042688985C500d26010a0Db1a356ad4D42474E
• Tokens:
  • CUPEX: 0x7C0E9E7C99E243DeD1336CD71b6AeBAc675Acd9C
  • USDC: 0x11cd09c968F584b5C8DCA760E73Bd39f1D3EeD72
  • DAI: 0x5bC52917D477c47961Ab06705b06Cbec636bCf21
  • NATIVE: 0x0000000000000000000000000000000000000000

XDC Testnet contracts deployed

XDC Testnet:

• CupexDEX: 0x32aD635dF78b7Ccfdb9593F121a2a1810973Ee31
• CupexStaking: 0x17cf676C3aC135e868D70c119CDD29f4aF9A4135
• Tokens:
  • CUPEX: 0x9B0da25b1cCEB8C9dBBd922c8bb41A25ac674626
  • USDC: 0xb116175B470a442EB7Fc82F78B2824bC203F4629
  • DAI: 0x8f17D881354C44507E42E37cAC10892633AFFFcF
  • NATIVE: 0x0000000000000000000000000000000000000000

Useful functions

• ERC20.balanceOf(wallet)
• cupexStaking:
  • function createStake(uint256 _amount) public
  • function unStake() public
  • function getStakeInformation() public view returns (StakeInformation memory) struct StakeInformation { uint256 timestampStaked; uint256 amountStaked; uint256 interest; }
• cupexDEX:
  • removeLiquidityPercent( IERC20 _tokenAddr, uint256 _percentLiquidityToRemove, address _transferTo ) public returns (uint256, uint256)
  • function getLiquidityByTokenAddr(IERC20 _token) public view returns (uint256, uint256)
  • function getListOfActiveTokens() public view returns (IERC20[] memory)
  • function addLiquidity( IERC20 _tokenAddr, uint256 _amountTokensIn, uint256 _amountCupexTokensIn, uint256 _minAmountTokensIn, uint256 _minAmountCupexTokensIn, address _transferTo ) public payable returns (uint256)
  • function removeLiquidity( IERC20 _tokenAddr, uint256 _amountOfLiquidityToRemove, uint256 _minAmountTokensOut, uint256 _minAmountCupexTokensOut, address _transferTo ) public returns (uint256, uint256)
  • Swap 100 USDC --> YYY DAI: function swapExactTokensForTokens( IERC20 _tokenIn, IERC20 _tokenOut, uint256 _amountTokensIn, uint256 _minAmountTokensOut, address _transferTo ) public payable returns (uint256)
  • Swap XXX USDC --> 100 DAI: function swapTokensForExactTokens( IERC20 _tokenIn, IERC20 _tokenOut, uint256 _maxAmountTokensIn, uint256 _amountTokensOut, address _transferTo ) public payable returns (uint256)
  • get XXX, 100 USDC --> XXX DAI: function getExactTokensForTokens( IERC20 _tokenIn, IERC20 _tokenOut, uint256 _amountIn ) public view returns (uint256)
  • get YYY, YYY USDC --> 100 DAI: function getTokensForExactTokens( IERC20 _tokenIn, IERC20 _tokenOut, uint256 _amountOut ) public view returns (uint256)