Leto is a decentralized full-stack lottery platform built on the Base (Sepolia) blockchain. Players purchase tickets for just 0.0002 ETH, selecting six unique numbers between 1-99. After a 7-day round, winning numbers are generated using Chainlink's Verifiable Random Function, ensuring provable fairness.
Leto is a fully decentralized lottery system running on the Base (Sepolia) blockchain. Leto leverages smart contract to create a transparent, fair, and automated lottery platform where all operations—from ticket purchases to prize distribution—are handled by a smart contract.
- Developed using Solidity 0.8.26 with a comprehensive state management system
- Implemented a multi-phase lottery process (Active, Drawing, Registration, Claiming)
- Integrated Chainlink VRF (Verifiable Random Function) for truly random, verifiable drawing results
- Utilized Chainlink Automation for managing time-based state transitions without manual intervention
- Incorporated robust error handling and validation systems for ticket purchases and prize claims
- Random number generation using Chainlink's VRF to ensure provable fairness
- Automated round management that extends the lottery if minimum participation thresholds aren't met
- Two-step winning process requiring winners to actively register tickets, preventing unclaimed prizes
- Prize pool rollover system when no winners are present
- Gas-efficient operations using unchecked math operations where appropriate
- Comprehensive event emission for front-end synchronization
- Built with Next.js for server-side rendering and optimal performance
- Styled using Tailwind CSS for responsive, modern UI design
- Real-time blockchain interaction through viem and wagmi
- User-friendly interfaces for ticket purchases, checking results, and claiming prizes
Users purchase tickets by selecting six unique numbers between 1-99. Each ticket costs 0.002 ETH. The lottery runs in weekly rounds with automated drawing using verifiably random numbers. Winners must register their tickets within a 3-hour window to claim their share of the prize pool, which consists of all ticket purchases minus a small 1% fee.
- Implementing secure random number generation on blockchain (solved with Chainlink VRF)
- Creating automated yet fair round transitions without human intervention
- Designing an efficient winner verification and prize distribution system
- Optimizing for gas costs while maintaining complete functionality
Import functions in the smart contract have been tested thoroughly using foundry
- Blockchain: Base (Sepolia)
- Smart Contracts: Solidity
- Testing Framework: Foundry
- Frontend: TypeScript, Next.js, TailwindCss, ConnectKit, Viem, Wagmi
- Backend: Express.js, Redis,