ReputationFi

ReputationFi is a decentralized platform that converts GitHub contributions into verified on-chain reputation tokens that serve as financial collateral for DeFi activities. The project bridges the gap between developer productivity and financial utility by creating a fair, verifiable system for valuing technical contributions.

Our platform solves a critical problem: developers build valuable open source contributions but can't leverage this reputation for financial access. ReputationFi transforms these contributions into quantifiable, verified assets on Flow blockchain using a quadratic scoring formula that evaluates commits, pull requests, and repository stars.

The system features three core components:

1. Verified Reputation Minting: Users connect their GitHub accounts through OAuth to verify their identity and contributions. This verification is critical to ensuring the integrity of reputation scores, as only verified GitHub data can be used to mint tokens.

2. Reputation-Backed Credit: Developers with reputation scores above a 1000-point threshold become eligible for credit lines. The borrowable amount is calculated using a logarithmic formula that scales with reputation score while maintaining risk management.

3. Reputation Staking: Users can stake their reputation tokens to earn yield (12% APY), demonstrating long-term commitment to their projects while generating returns.

Built on Flow blockchain using Cadence's resource-oriented programming model, ReputationFi leverages Flow's security, low transaction costs, and scalability. Our smart contracts implement secure vaults for reputation tokens and capability-based security for controlled access.

ReputationFi creates a new primitive for DeFi: using developer contributions as intangible collateral. This opens financial access to millions of developers worldwide who have valuable skills and contributions but may lack traditional financial resources or credit history.

ReputationFi was built using a combination of modern web technologies and Flow blockchain, leveraging the unique capabilities of Cadence's resource-oriented programming model.

Technical Stack

• Frontend: Next.js React application with TypeScript for type safety
• Blockchain: Flow blockchain for its performance, low fees, and resource-oriented programming
• Smart Contracts: Cadence smart contracts for reputation token minting and vault management
• Authentication: Dual authentication system using FCL for Flow wallet connection and GitHub OAuth
• Deployment: Vercel for the frontend, Flow testnet for smart contracts

Core Implementation Details

The heart of ReputationFi is our Cadence smart contract that implements two key resource types:

1. RepToken Resource: Contains verified GitHub metrics and computed reputation score
2. ReputationVault Resource: Securely stores reputation tokens with capability-based security

We leveraged Cadence's resource-oriented programming model, which ensures tokens exist in exactly one location and cannot be duplicated—critical for maintaining the integrity of reputation scores.

GitHub Integration

Our GitHub verification system uses OAuth to authenticate users and fetch their contribution statistics. This ensures that only the actual owner of a GitHub account can mint reputation tokens based on their contributions. The verification process:

1. Initiates GitHub OAuth flow with minimal required permissions (read:user)
2. Stores authentication tokens securely
3. Retrieves metrics via GitHub's GraphQL API: commits, pull requests, stars
4. Uses these verified metrics for reputation calculation

Reputation Calculation

We implemented a quadratic scoring formula to prevent gaming the system:

score = (sqrt(commits) * 50) + (sqrt(pullRequests) * 100) + (sqrt(stars) * 30)

This formula weights different contribution types appropriately while reducing the impact of extreme outliers.

DeFi Features

The credit system uses a logarithmic formula that calculates borrowable amounts based on reputation:

borrowableAmount = baseAmount + (scaleFactor * log10(score - threshold + 100) * 100)

This creates a fair scaling system where reputation growth translates to increased credit access but at a diminishing rate to manage risk.

Challenges Overcome

The biggest challenge was creating a system that couldn't be gamed. By requiring GitHub verification and implementing quadratic scoring, we ensured reputation tokens genuinely reflect development contributions.

We also faced Flow emulator connectivity issues during development, which we resolved by implementing fallback mechanisms for demo purposes while maintaining the integrity of the core smart contract design.

Flow-Specific Benefits

Flow's resource-oriented programming enabled us to create a secure, non-fungible representation of reputation that cannot be duplicated or forged. The capability-based security model allowed us to control access to tokens while enabling public verification, critical for a reputation system.