CredChain

What this project is This is a referral-powered credit network that combines on-chain behavior with off-chain credit data to produce a composite credit score. When a user improves their credit standing, a portion of that “credit gain” cascades up to the people who referred them. The result is an incentive-aligned system where good financial behavior strengthens both the individual and the trust network that vouched for them. Why it exists Traditional credit is siloed and slow to update, and it doesn’t capture community knowledge. In emerging markets, new-to-credit users, and crypto-native contexts, there’s valuable signal in wallet histories and social trust. This project turns those signals into a transparent, auditable score, while keeping humans (lenders, program admins) firmly in control. How it works, end to end Identity and wallets A user creates an on-chain profile and links one or more wallets to a single identity (web3Id). This supports realistic usage where people operate multiple wallets. Referrals and approvals Users invite others by email. The invited user accepts on-chain, creating an explicit referral edge. Approval is deliberate: referrers choose whom they’re willing to vouch for. Scoring inputs On-chain: the system analyzes wallet activity (e.g., tenure, stable balances, repayment-like behaviors in supported protocols). Off-chain: it integrates a traditional bureau score via Flare FDC’s Web2JSON flow (Experian mocked for the demo). These are combined into a composite score with configurable weights. Reward propagation When a user’s score increases due to positive behavior, a portion of that improvement propagates up their referral paths. If multiple referrers or paths exist, the upstream rewards accumulate. This makes the network effect visible and measurable. Data and indexing Smart contracts store referral relationships and key events on-chain. IPFS persists supplemental data where appropriate. The Graph indexes contract events into a subgraph so the frontend can query networks, rewards, and stats efficiently. Frontend and modes A Next.js app with ethers.js and MetaMask supports two modes: Live mode for real contract interactions.

Who benefits Users grow their own credit while benefiting from the positive behavior of people they vouch for. Referrers earn network rewards for making good introductions. Lenders and platforms get a richer, more transparent scoring signal that blends traditional credit with verifiable on-chain history.

Smart contracts: ReferralCreditNetwork.sol handles referrals, approvals, and propagation events. UserCreditRegistry.sol manages identity and scoring data. Indexing and storage: The Graph subgraph for entities such as Users, Referrals, and RewardEvents. IPFS for decentralized persistence of non-critical artifacts. Backend services: Express server integrating Flare FDC Web2JSON to pull (mocked) Experian data. Simple API endpoints for invitation emails and off-chain components. Frontend: Next.js + ethers.js + MetaMask. wallet linking, referral creation, score views, and network explorer.