Yield Drip

YieldDrip is a DeFi application that solves the capital inefficiency problem in traditional Dollar-Cost Averaging (DCA). When users set up a DCA strategy to buy ETH over time, their idle capital typically sits in a wallet earning nothing. YieldDrip changes this by immediately depositing all capital into a yield-bearing vault (sDAI) and withdrawing funds just-in-time for each purchase.

The system works through three core smart contracts:

• YieldDepositHelper: Immediately deposits user's DAI into sDAI vault to start earning yield
• YieldWithdrawHelper: Withdraws exact amounts needed for each trade, keeping remaining funds earning yield
• LinearTwapGetter: Calculates proportional amounts for each time slice using Time-Weighted Average Price

Users create a single EIP-712 order that generates 24 separate limit orders on 1inch's Limit Order Protocol. Each order includes custom predicates for time-based execution and price floor protection using Chainlink feeds. The system automatically skips purchases when ETH price exceeds user-defined limits, keeping funds earning yield until prices become favorable.

Key innovations:

• Zero opportunity cost: 100% capital utilization vs ~50% in traditional DCA
• Real yield earning: sDAI provides 3-5% APR on idle capital
• Price protection: Smart predicates prevent overpaying
• Single signature: One EIP-712 signature creates entire DCA strategy

The frontend provides real-time strategy monitoring, yield analytics, and manual execution controls for demo purposes.

YieldDrip is built using a modern DeFi stack with real smart contract integration:

Smart Contracts (Solidity + Foundry):

• YieldDepositHelper: Handles DAI to sDAI conversion for immediate yield earning
• YieldWithdrawHelper: Manages just-in-time DAI withdrawal for order execution
• LinearTwapGetter: Calculates dynamic amounts for each time slice using TWAP
• MockERC4626Yield: Simulates yield-bearing vault functionality for testing
• Comprehensive test suite with Foundry for security validation

Frontend (Next.js + TypeScript + Wagmi):

• Real 1inch Limit Order SDK integration using @1inch/limit-order-sdk
• Custom React hooks (use1inchIntegration) for seamless DeFi interaction
• Wagmi for wallet connection and EIP-712 signature handling
• Real-time order monitoring with WebSocket integration
• Modern UI with Tailwind CSS and shadcn/ui components

Key Technical Achievements:

• Direct integration with 1inch LOP v4 using official SDK
• Custom SDK implementation for direct contract interaction
• EIP-712 structured data signing for secure order creation
• Predicate-based order execution with Chainlink price feed integration
• Real-time yield tracking with live sDAI balance monitoring

Deployment & Infrastructure:

• Foundry-based deployment system with comprehensive scripts
• Base Sepolia testnet deployment with contract verification
• Environment-based configuration for seamless testnet/mainnet switching
• Docker-ready backend architecture for production scaling

The system demonstrates advanced DeFi concepts including yield farming, automated market making, and cross-protocol integration while maintaining excellent UX through single-signature strategy creation.