Fusion Jar

Problem Statement

🧪 Fusion Jar — DescriptionFusion Jar is a gamified, gasless, cross-chain micro-investment platform built on top of 1inch Fusion+ and powered by Privy wallets. It allows users to automate recurring, low-cost crypto investments (e.g., $1–$10) across major EVM chains (Ethereum, Base, Polygon, Arbitrum) without worrying about gas fees, chain switching, or complex wallet management.The goal is to democratize DeFi by making long-term crypto investing as easy as setting up a recurring deposit — even for beginners. Users can create personalized “Jars” (intent-based investment plans), which execute periodic token swaps using the gasless, decentralized auction-based Fusion+ protocol.Key FeaturesRecurring Micro-Investments ("Jars")Users define:Amount to invest (e.g., $1 every week)Target token (e.g., ETH, MATIC, OP)Chain (e.g., Polygon, Base)Frequency (Daily, Weekly, Monthly, or Custom)The system periodically executes the swap using 1inch Fusion+, which means:No gas feesNo relayers or batchingBest execution price via auctionSmart Wallet Integration (via Privy)Fusion Jar leverages Privy’s embedded smart wallets, giving every user a gasless, non-custodial wallet experience without needing MetaMask.Users sign in via email or OAuth.Wallets are controlled by the user and stored securely via Privy, enabling seamless recurring execution.Cross-Chain ExecutionUsers can invest in tokens across multiple chains from a single UI.Fusion+ supports native token swaps on Base, Polygon, Ethereum, and Arbitrum.The system checks balances and executes the intended swaps periodically per Jar configuration.Gamification LayerEvery successful Jar execution gives users:XP pointsStreaks for continuous investmentBadges for milestones (e.g., “7-Day Streak”, “Early Minter”)This boosts engagement, retention, and makes investing fun.Customization & Power User ControlsUsers can:Name their Jars (e.g., "My ETH DCA")Set slippage tolerance, deadline, and execution time windowView swap history and performance per JarEnable/disable individual JarsHow It WorksUser signs in via Privy.Creates a Jar with desired configuration (e.g., $5 every Monday into ETH on Base).Approves token (if needed) for USDC (or any supported token).A cron job on the backend monitors all active Jars every 30 minutes:Checks wallet balanceBuilds Fusion+ swap quoteSigns and submits the transaction using the user's Privy walletStores execution logs in the databaseGamified feedback and XP are updated per execution.Why Fusion Jar?Solves DeFi UX and onboarding problems by abstracting away:GasChain switchingManual wallet actionsEncourages financial consistency and disciplineMakes recurring investing accessible, cheap, and even fun

Solution

Fusion Jar is built as a full-stack Web3 product with deep integration into 1inch Fusion+, Privy, and multiple EVM-compatible chains. Below is a breakdown of how the system is architected and implemented:Frontend:The UI is built using Next.js with TailwindCSS and shadcn/ui for minimal, modern component styling.It includes dynamic form builders for creating "Jars" (micro-investment intents) and a dashboard to view streaks, XP, performance, and execution logs.Wallet connection and authentication are powered by Privy, allowing users to sign in via email or OAuth and get access to an embedded smart wallet with no setup.Backend:The backend is a Node.js and TypeScript app using Express and cron-based services.A scheduled cron job runs every 30 minutes, querying theinvestment_intentstable for active intents.For each active Jar:It checks the user's Privy smart wallet balance on the respective chain.If funds are sufficient, it fetches a Fusion+ quote using the 1inch API (with our partner access key).It signs and submits the transaction using the Privy wallet's private key.Logs the transaction to theinvestment_executionstable, tagging it as success or failure.Partner Tech Integrations:1inch Fusion+: The entire gasless, auction-based swapping mechanism is built on top of 1inch’s Fusion+ protocol. It allows decentralized execution with optimal pricing and no relayers or batching hacks. Their SDK and partner API access enabled faster prototyping.Privy: Privy smart wallets made the product possible. It enabled gasless, non-custodial wallets for every user without requiring them to install MetaMask. We store wallet metadata securely and use wallet keys for executing scheduled swaps.QuickNode and Alchemy: Used as RPC providers for accessing multiple EVM chains and monitoring wallet balances.Notable Hacks:We wrote a multi-chain wallet checker and gasless swap builder that can dynamically adjust quotes across Ethereum, Polygon, Base, and Arbitrum, choosing the best time for execution depending on Fusion+ liquidity.Fusion Jar simulates “subscription-style investing” without ever needing ongoing user interaction. All actions — signing, execution, retries — happen fully server-side in a secure way via Privy.The gamification engine runs in parallel: for every successful execution, it awards XP, updates streaks, and assigns badges — all tracked in a dedicated engagement table.Overall, the project bridges real DeFi infrastructure with seamless UX and growth mechanics, using 1inch Fusion+ and Privy as the technical backbone.