ChainFlow Factor

Inspiration

• Supply-chain financing is slow and opaque; we wanted a transparent, on-chain rail where invoices become verifiable, fundable assets.
• SMEs struggle to prove invoice legitimacy and unlock capital quickly—tokenizing invoices with lightweight verification bridges that gap.

What it does

• Turns invoices into NFTs that carry amount, due date, and state (verified, funded, repaid).
• Verifies invoices via oracle or ZK mock before funding.
• Pools investor liquidity to fund verified invoices and charges a flat 5% interest on repayment.
• Distributes interest proportionally to investor balances; investors can withdraw deposit + earned interest.

How we built it

• Smart contracts: Solidity + Hardhat + OpenZeppelin. Contracts: InvoiceNFT, LendingPool, MockOracle, MockVerifier.
• Frontend: Next.js, TypeScript, Tailwind, framer-motion, wagmi/viem, RainbowKit for wallets.
• Flow: Issuer mints and verifies → pool funds → issuer repays principal + 5% → pool distributes interest to investors → investors withdraw.

Challenges we ran into

• Ensuring interest distribution updated actual investor balances (not just virtual shares).
• Keeping contract/ABI addresses in sync across redeploys.
• Handling wallet UX (MetaMask flow, retries, and error surfacing) for funding/repay/withdraw.

Accomplishments that we're proud of

• Working end-to-end flow: mint → verify → fund → repay with automatic interest distribution → withdraw.
• Simple flat-rate model with clear, proportional interest sharing for investors.
• Clean dual-role UI for issuers and investors in one app.

What we learned

• Importance of syncing contract addresses and reflecting on-chain balances in the UI.
• Clear error handling and state refresh are critical for multi-step DeFi flows.
• Flat-rate interest keeps UX simple for a demo, while still exercising funding/repay mechanics.

What's next for ChainFlow Factor

• Real oracle/attestor integrations and production ZK proofs.
• Dynamic risk-based interest rates and tranche-style pools.
• Invoice marketplace filtering by risk/tenor and partial fills.
• Audits, monitoring, and improved wallet/user guidance.

Built With

• chainlink
• ethers.js
• hardhat
• ipfs
• javascript
• next.js
• openzeppelin
• polygon
• react
• solidity
• tailwind-css