Synapse Yield

The Synapse Yield platform was conceived, designed, and built entirely from scratch during the MetaMask Smart Accounts × Monad Dev Cook Off. All components—from the smart account backend to the polished frontend—were developed within the hackathon period. We first ideated a non-custodial, automated yield optimizer to simplify complex DeFi operations and designed a full-stack architecture built on the Monad Testnet using ERC-4337 Smart Accounts as the core user identity layer, enhanced by the MetaMask Delegation Toolkit for secure and permissioned automation. We then implemented ERC-4337 Smart Account generation, deployment, and management using permissionless.js and the Pimlico bundler/paymaster. Non-custodial, scoped delegations were created using the MetaMask Delegation Toolkit to enable automated actions without exposing user keys. Authentication was secured through SIWE (Sign-In With Ethereum) and Iron Session. On the frontend, we built a complete application using Next.js (App Router), React, TypeScript, and Tailwind CSS, including a multi-section landing page with 3D models and Framer Motion animations, plus key sections like Dashboard, Onboarding, Fund Management, Staking, Swapping, and the Yield Optimizer control panel. On the backend, we developed Next.js API Routes to handle delegated transactions, session management, and database operations, along with the keeper automation script (src/scripts/keeper.ts) to fetch balances, compute rebalancing logic, and execute delegated swaps every 5 minutes using FastCron. We integrated MongoDB for secure data storage and the Envio indexer for a real-time on-chain activity feed. Finally, the entire full-stack application, including automation via FastCron, was deployed to Vercel for live public demonstration.