Firework

Firework is a cross-chain yield optimization protocol that allows users to earn the best available APY across multiple chains and lending protocols—all with a single click and no prior DeFi experience required. Users deposit USDC on Worldchain, and Firework seamlessly handles everything else: converting it into IzUSD (a yield-bearing synthetic stablecoin), routing it through the IzUSD Gateway, and allocating it to the most profitable lending opportunities across chains like Mantle and Flow. Behind the scenes, Firework constantly monitors APY fluctuations across protocols such as Morpho, Lendle, and More.Markets. It dynamically updates positions to maintain optimal yield, ensuring that users’ capital is always working as efficiently as possible. Withdrawals are just as simple: users receive their original funds plus accrued yield, directly back on Worldchain, abstracting away all of the cross-chain complexity and gas juggling. By automating the entire DeFi strategy layer, Firework makes advanced yield farming accessible, efficient, and user-friendly.

Firework is built on a modular, cross-chain architecture using standardized smart contract components and custom logic for real-time APY analysis and routing. At its core, it leverages the ERC-4626 vault standard to manage deposits and withdrawals in a uniform way across all supported chains. The vaults interact with external lending protocols (e.g., Morpho on Worldchain, Lendle on Mantle) to mint and manage IzUSD, a synthetic stablecoin representing yield-bearing positions. The IzUSD Gateway serves as the bridge logic between chains, handling smart contract calls and transfers via cross-chain messaging protocols (e.g., LayerZero or Axelar, depending on integration needs). Position updates and APY monitoring are handled through a set of off-chain bots that continuously fetch on-chain data and trigger reallocation logic via automation frameworks like Chainlink Keepers or Gelato. One particularly clever hack was the stateless abstraction of user positions: rather than tracking user state across chains, Firework tokenizes vault shares and relies on IzUSD as a unified accounting layer, which drastically reduces state management complexity. All this allows for fast, gas-optimized rebalancing and an elegant UX that hides the multi-chain operations behind a single, seamless interface.