NoCap-Lottery

NoCap Lottery is a no-loss lottery protocol where users enter weekly draws by depositing funds without ever risking their principal. In the MVP, deposits are pooled into conservative DeFi lending markets through ERC-4626 to generate real yield, and only the interest earned is distributed as prizes. When yields are low, prize size and frequency adjust naturally, avoiding leverage or speculative strategies.

Principal safety is by design: User deposits remain redeemable at all times and are never traded. If the yield source fails, prize draws pause and the protocol prioritizes transparency and capital preservation. Unlike earlier prize-savings systems, NoCap Lottery focuses on cross-chain access, simple fairness mechanics and sustainable engagement rather than large jackpots or yield chasing, giving users a reason to stay even when they don’t win.

NoCap Lottery is a modular, on-chain protocol that separates yield generation, prize logic and user interaction to ensure safety and transparency.

Asset-specific ERC-4626 vaults are used for stablecoins, ETH/WETH and BTC-based assets to avoid directional exposure, with deposits supplied into conservative lending markets. A separate lottery contract distributes only the accrued yield through weekly lotteries, where users enter by depositing a fixed $100 ticket amount, while the principal remains redeemable at all times.

We have integrated several partner technologies to improve UX and trust:

• LI.FI is used to unify cross-chain deposits into the correct asset pool without fragmenting liquidity.

• ENS is integrated as an identity layer, allowing participants and winners to appear as human-readable names with profiles and history instead of hexadecimal addresses, increasing trust and social clarity.

• Yellow Network is used for session wallets, enabling gasless, fast interactions such as purchasing multiple tickets during the deposit window.

Winner selection uses Chainlink VRF to ensure provably fair, manipulation-resistant randomness and real-time yield generation is surfaced via on-chain data visualized in the UI.

Notable Hack:

• For the demo, we built a dedicated smart-contract flow that simulates the full protocol lifecycle end-to-end using real contract calls, allowing judges to experience deposits, yield accrual, randomness and prize distribution exactly as they would work in production.

• To improve retention, 1% of weekly yield is accumulated into a larger monthly prize, giving users an incentive to stay engaged even if they don’t win weekly draws.