Warranty Pass

Demo

About

WarrantyPass is a consumer app that helps people keep track of product receipts, warranty coverage, and purchase history in one place. Instead of losing a paper receipt or digging through old emails months later, users can upload a receipt, have AI extract key purchase details such as the product, retailer, purchase date, and price, review the information, and create a digital WarrantyPass for the item. Each WarrantyPass shows important warranty information, including the coverage period, expiration date, remaining time, retailer, and whether the warranty is transferable. Receipt images and sensitive purchase information stay private in secure storage rather than being published onchain. For added integrity, WarrantyPass can create a tamper-evident proof on Ethereum Sepolia. The original receipt file is cryptographically hashed, and only the hash, an opaque product identifier, warranty dates, transferability information, and the wallet that registered the proof are recorded in the smart contract. WarrantyPass then reads the record back from the blockchain and verifies that it matches the locally stored receipt and warranty data. The goal of WarrantyPass is to make warranties easier to manage today while creating a foundation for portable product history in the future. When products are resold, their purchase history, repair records, and eligible warranty rights could move with them, giving buyers more confidence in secondhand purchases while keeping private information offchain.

How it's made

WarrantyPass is built as a React + Vite + TypeScript application with Tailwind CSS for the UI. Supabase powers the backend, including anonymous authentication, Postgres, Row Level Security, and private Storage for receipt images. Users can either enter product details manually or upload a receipt. Receipt images are sent through a Supabase Edge Function, where a vision-capable AI model extracts structured product information such as the brand, model, retailer, purchase date, and price. The user always reviews and confirms the extracted information before a WarrantyPass is created. Sensitive data stays offchain. The original receipt file is stored privately in Supabase and is never exposed publicly. For the blockchain layer, WarrantyPass hashes the exact original receipt bytes using `keccak256`, then stores only the resulting hash and minimal warranty metadata in a custom `WarrantyPassRegistry` smart contract deployed on **Arc Testnet**. The contract records an opaque product key, receipt hash, purchase date, warranty expiration, transferability flag, and the wallet that registered the proof. It intentionally does not store serial numbers, personal information, receipt images, or other sensitive data onchain. The frontend uses wagmi and viem for wallet connection, Arc Testnet network handling, contract reads, transaction simulation, writes, and confirmation tracking. Before submitting a transaction, the app checks whether the product has already been registered to avoid duplicate proofs. After confirmation, WarrantyPass reads the contract record back from Arc Testnet and compares it against the local receipt hash and warranty data. The UI only shows the proof as verified if the values match. One of the more important design choices was keeping Supabase identity and wallet identity separate. Supabase controls access to private user data through RLS, while the connected wallet is only used to sign blockchain transactions. This avoids treating wallet connection as application authentication and keeps private consumer data protected. The result is a hybrid architecture where AI makes receipt onboarding fast, Supabase handles private user data and application state, and **Arc provides the tamper-evident onchain proof layer** without putting personal information onchain.