what's Défi?

Défi is a gamified 1v1 live DeFi trading competition platform built on Ethereum Layer 2 networks such as Arbitrum and Base. Players compete in timed duels by opening leveraged perpetual positions on-chain via Gains Network smart contracts. The winner is determined solely by achieving the higher profit-and-loss (PnL) percentage when the duel timer expires, ranging from 60 seconds to 7 days. Onboarding is frictionless with server-side MPC wallets created via Dynamic SDK, allowing users to stake any ERC20 token, which is automatically swapped to USDC collateral using Uniswap API quotes. The platform supports two modes: Friendly (testnet with faucet USDC for risk-free practice) and Duel (mainnet with real stakes). Real-time PnL updates, position monitoring, and event listening (e.g., trade executions) are handled by a NestJS backend with WebSocket streaming from Gains Network price feeds across chains. Frontend uses Next.js 16 with React 19 and Tailwind CSS, ensuring verifiable, trustless trades. This lowers barriers to on-chain perp trading while teaching core mechanics through competitive gameplay.

Défi is a top 10 finalist at ETHGlobal Cannes hackathon.