dart_web3_swap

A unified DEX aggregation layer for Dart. Perform asset swaps, fetch liquidity quotes, and interact with numerous decentralized exchanges (Uniswap, PancakeSwap, 1inch) through a single interface.

🚀 Features

• Smart Route Discovery: Connect to aggregators to find the best price across multiple liquidity pools.
• Price Impact Analysis: Pre-calculate slippage and impact to protect user funds.
• Protocol Support: Specialized modules for Uniswap v2/v3, Curve, and Balancer.
• Atomic Operations: Bundle approval and swap transactions where the protocol supports it.

Usage Flow

graph LR
    A[Token In/Out] --> B[Quote Engine]
    B --> C[Fetch 1inch/Uniswap]
    C --> D[Compare Routes]
    D --> E[Best Quote]
    E --> F[Encoded Tx]
    F --> G[Approval + Swap]

🏗️ Architecture

graph TD
    User[Swap Intent] --> Aggregator[Swap Engine]
    Aggregator --> Q1[1inch API]
    Aggregator --> Q2[Uniswap v3 SDK]
    Aggregator --> Q3[0x Protocol]
    
    Aggregator --> BestQuote[Winner]
    BestQuote --> Tx[Encoded Transaction]

📚 Technical Reference

Core Classes

🛡️ Security Considerations

• Slippage Protection: Never hardcode slippage to 0%. Always allow for a reasonable buffer (e.g., 0.5% - 1.0%) to prevent transaction reverts in volatile markets.
• Infinite Approval Risk: Only approve the exact amount needed for a swap if your threat model involves high-risk or un-audited protocols.
• MEV Awareness: For large swaps, use modules like dart_web3_mev to route transactions through private builders and avoid front-running.

💻 Usage

Fetching a Quote from 1inch

import 'package:dart_web3_swap/dart_web3_swap.dart';

void main() async {
  final engine = SwapEngine(apiKey: '...');
  
  final quote = await engine.getQuote(
    fromToken: '0x...', // USDC
    toToken: '0x...',   // ETH
    amount: EthUnit.parseUnit('100', 6),
    slippage: 0.01, // 1%
  );

  print('Estimated Return: ${quote.toTokenAmount}');
  print('Transaction Required: ${quote.txData}');
}

📦 Installation

dependencies:
  dart_web3_swap: ^0.1.0