> For the complete documentation index, see [llms.txt](https://docs.boom.market/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.boom.market/boom-blockchain/boomswap/developer.md).
# Developer
Boomswap is a [Uniswap V2](https://docs.uniswap.org/contracts/v2/overview) fork. Developers can interact with Boomswap in the same way they use Uniswap repositories and SDKs.
{% hint style="info" %}
Boomswap has a total **fee structure** of **1.9%** from which 0.3% goes to the protocol.
{% endhint %}
The following steps were made when forking the original code:
## V2-Core-Master Module
### Contracts and Modifications
* **BoomswapERC20.sol** : Originally [`UniswapV2ERC20`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/Pair-ERC-20), this contract has been modified for LP name and symbol adjustments.
* **BoomswapPair.sol** : Originally [`UniswapV2Pair`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/pair). Fee value in updated in the `BoomswapPair-swap()` function at these two lines:
```solidity
// 19 = 1.9% fee
uint256 balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(19));
uint256 balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(19));
```
* **BoomswapFactory.sol**: Formerly [`UniswapV2Factory`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/factory). Key modification includes the initialization of the state variable `INIT_CODE_HASH`. The deployment of this contract requires a specified `_feeToSetter` address, which has the authority to adjust the `feeTo` parameter.
## V2-Periphery-Master Module
### Implementation Steps
1. Retrieve the contract address and `INIT_CODE_HASH` from the deployed Factory.
2. In [`UniswapV2Library.sol`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/library), replace the existing init code hash in the `pairFor` function (Remove the '0x' prefix).
3. Compile and deploy the `IUniswapV2Router02` and **`BoomswapRouter.sol`** contracts (previously [`UniswapV2Router02`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02)) using the appropriate pragma solidity version.
4. **BoomswapRouter Deployment**: Requires the `_FACTORY` address and the WBMC address (formerly WETH).
Consider modifying `UniswapV2Library.sol` and `UniswapV2LiquidityMathLibrary.sol` fees initially at 0.3% (997/1000).
{% hint style="danger" %}
Don't subsitute WETH with WBMC. Maintain the convention usage of ETH everywhere in the code: in names like *IWETH*, *amountETHMin*, etc.
{% endhint %}
## API Endpoints Documentation
Don't forget to approve token before calling any of the following endpoints.
### [🔗 Pair Interaction](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/factory#createpair)
* [Create Pair](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/factory#createpair)
* [Get Pair](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/factory#getpair)
### [🔗 Providing Liquidity](https://docs.uniswap.org/contracts/v2/guides/smart-contract-integration/providing-liquidity)
* Use [`addLiquidity`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#addliquidity) for ERC-20/ERC-20 pairs.
* For WBMC pairs (WETH convention), use [`addLiquidityETH`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#addliquidityeth).
* To remove liquidity, use [`removeLiquidity`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#removeliquidity) or [`removeLiquidityETH`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#removeliquidityeth).
* For withdrawal estimates, follow the logic in [`UniswapV2Pair-burn()`](https://github.com/Uniswap/v2-core/blob/master/contracts/UniswapV2Pair.sol).
### [🔗 Swap Operations](https://docs.uniswap.org/contracts/v2/guides/smart-contract-integration/trading-from-a-smart-contract)
* [`swapExactTokensForTokens`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#swapexacttokensfortokens)
* [`swapTokensForExactTokens`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#swaptokensforexacttokens)
* [`swapExactETHForTokens`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#swapexactethfortokens)
* [`swapTokensForExactETH`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#swaptokensforexacteth)
* [`swapExactTokensForETH`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#swapexacttokensforeth)
* [`swapETHForExactTokens`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#swapethforexacttokens)
### [🔗 Pricing](https://docs.uniswap.org/contracts/v2/concepts/advanced-topics/pricing#pricing-trades)
* **Quotation**: Use [`quote`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#quote).
* **Exact Output**: Use [`getAmountOut`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#getamountout) | [`getAmountsOut`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#getamountsout).
* **Exact Input**: Use [`getAmountIn`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#getamountin) | [`getAmountsIn`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02#getamountsin).
* **Pair Reserves (TVL)**: Use [`getReserves`](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/pair#getreserves).
### Resources
* [Uniswap V2 Router Contracts Documentation](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/router-02)
* [Uniswap V2 Factory Contracts Documentation](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/factory)
* [Uniswap V2 Libraries Documentation](https://docs.uniswap.org/contracts/v2/reference/smart-contracts/library)
***
{% content-ref url="/pages/FBqVw68OYEhBLncrvvu8" %}
[Contracts](/reference/contracts.md)
{% endcontent-ref %}