FlexFi - Crypto-Backed BNPL Protocol

The freedom to pay with crypto, later.

FlexFi is a revolutionary Solana-based protocol that enables Buy Now, Pay Later (BNPL) transactions backed by cryptocurrency collateral. Unlike traditional BNPL services, FlexFi eliminates debt traps by requiring users to stake crypto assets as collateral.

🌟 Key Features

💰 Collateral-Backed BNPL

• No toxic debt - Every payment is collateral-backed
• Automatic liquidation - No late fees, just collateral forfeit
• Flexible payment terms - 3, 4, 6, 12, 18, 24, or 36 installments

🎯 Dynamic Credit Scoring

• Inclusive scoring - Your access grows as you use the platform
• Real-time updates - Score adjusts with payment behavior
• No bank dependency - Fully sovereign credit system

💎 Multi-Tier Card System

• Standard (Free): 7% fees, 3-6 month terms
• Silver ($50/year): 4% fees, up to 12 months
• Gold ($150/year): 3.5% fees, 0.5% cashback
• Platinum ($300/year): 3% fees, 1.5% cashback

🎨 NFT Enhancement System

• Bronze/Silver/Gold NFTs enhance card benefits
• Reduced fees and increased limits
• Unique utility beyond just aesthetics

📈 FlexYield Integration

• Earn on every purchase - Rewards invested automatically
• Multiple strategies - Staking, DeFi, RWA, Auto-compound
• Passive income while spending

🏗️ Architecture Overview

FlexFi Protocol Modules

🧩 Module	🎯 Purpose	🔧 Key Functions	💰 Financial Impact
🔐 Staking	Collateral Management	• Deposit USDC • Lock periods (7-365 days) • Auto-liquidation	Secures BNPL transactions
🛒 BNPL	Buy Now Pay Later	• Create payment plans • Process installments • Handle defaults	Core revenue generation
📊 Score	Credit Assessment	• Track payment history • Dynamic scoring (0-1000) • Risk evaluation	Determines user limits
💳 Card	User Tiers	• 4 tier system • Annual fee management • Benefit allocation	Subscription revenue
🎨 NFT	Enhanced Benefits	• Mint utility NFTs • Attach to cards • Dynamic perks	Premium user engagement
📈 Yield	Reward System	• Auto-invest rewards • Multiple strategies • Compound returns	User retention incentive

Data Flow Architecture

👤 User → 🔐 Whitelist Check → 💰 Stake Collateral → 🛒 BNPL Eligible
                ↓
📊 Score Tracking ← 💳 Card Benefits ← 🎨 NFT Enhancements ← 📈 Yield Generation

Security & Access Control

Layer	Component	Access Level	Purpose
Layer 1	Whitelist System	Admin-controlled	Platform access
Layer 2	Wallet Verification	User signature	Transaction auth
Layer 3	Collateral Check	Protocol logic	Risk management
Layer 4	Score Validation	Dynamic scoring	Credit limits

🚀 Quick Start

Prerequisites

• Rust (latest stable)
• Solana CLI tools
• Node.js (for tests)
• Git

Installation

# Clone the repository
git clone https://github.com/your-org/flexfi-web3.git
cd flexfi-web3

# Build the program
cargo build-bpf

# Run tests
npm run test

Deployment

# Deploy to devnet
solana program deploy target/deploy/flexfi_program.so

# Verify deployment
solana program show <PROGRAM_ID>

📖 Documentation

Core Modules

🔐 Whitelist System

All users must be whitelisted to use FlexFi functions:

// Initialize whitelist (admin only)
InitializeWhitelist

// Add user to whitelist
AddToWhitelist { user_pubkey }

💰 Staking Module

Users stake USDC as collateral for BNPL transactions:

// Deposit staking
DepositStaking { amount, lock_days }

// Withdraw staking (after lock period)
WithdrawStaking { amount }

🛒 BNPL Module

Create and manage Buy Now, Pay Later contracts:

// Create BNPL contract
CreateBNPLContract { 
    amount, 
    installments, 
    payment_interval_days 
}

// Make payment
MakeBNPLPayment

// Check for overdue payments
CheckRepayment

📊 Score Module

Track and manage user credit scores:

// Initialize score (50 points default)
InitializeScore

// Update score (automatic)
UpdateScore { change }

// Get current score
GetScore

🧪 Testing

Test Structure

tests/
├── 1-verify-wallet-whitelisted.js  # Verify wallet whitelist status
├── 2-test-staking-with-backend.js  # Test staking functionality
└── 3-test-score.js                 # Test credit score system

Running Tests

# Install dependencies
npm install

# Run individual tests
node tests/1-verify-wallet-whitelisted.js
node tests/2-test-staking-with-backend.js
node tests/3-test-score.js

🎯 User Journeys & Scenarios

🆕 Scenario 1: New User Onboarding

The Journey: From Registration to First BNPL

flowchart TD
    A[👤 User visits FlexFi] --> B[📝 Register with Email]
    B --> C[🔑 Backend creates wallet]
    C --> D[✅ Admin adds to whitelist]
    D --> E[💰 User stakes 100 USDC]
    E --> F[📊 Score initialized: 50 pts]
    F --> G[💳 Choose card tier]
    G --> H[🛍️ Ready for BNPL!]
    
    style A fill:#e1f5fe
    style H fill:#c8e6c9

Loading

Step-by-Step Breakdown:

Step	Action	Who	Result
1	User registers	User	Account created
2	Wallet generation	Backend	New Solana wallet
3	Whitelist addition	Admin	Access granted
4	Stake collateral	User	100 USDC locked 30 days
5	Score initialization	System	50 credit points
6	Card selection	User	Silver card active
7	BNPL eligibility	System	Up to 100 USDC available

---

🛒 Scenario 2: BNPL Purchase Journey

The Journey: Buy Now, Pay Later in Action

Payment Flow Details:

💰 Purchase: $30 sneakers
📊 Split: 3 payments of $10.33 each
🏦 Collateral: 100 USDC staked
💳 Card: Silver (4% fee = $1.20)

Timeline:
Week 1:  ✅ Merchant gets $30 instantly
Week 4:  ✅ Payment 1 ($10.33) - Score: 505
Week 9:  ❌ Payment 2 missed - Auto-debit from staking - Score: 485  
Week 12: ✅ Payment 3 ($10.33) - Contract complete - Score: 505

---

📈 Scenario 3: FlexYield in Action

The Journey: Earning While Spending

FlexYield Mathematics:

🔹 Purchase: $100 coffee machine
🔹 Gold Card: 0.5% cashback = $0.50
🔹 Strategy: AutoCompound Staking
🔹 APY: ~8% annually

Monthly progression:
Month 1: $0.50 → Stake
Month 2: $1.03 → Compound  
Month 3: $1.59 → Compound
Month 6: $3.24 → Available to claim

---

🎴 NFT Enhancement Scenario

The Journey: Upgrading with NFTs

Before vs After NFT:

Feature	Silver Card	Silver + Bronze NFT
BNPL Fee	4%	3.5%
Credit Limit	Standard	+10%
Perks	Basic	Priority processing
Visual	Standard design	Custom NFT art

🔧 Configuration

Environment Variables

SOLANA_RPC_URL=https://api.devnet.solana.com
FLEXFI_PROGRAM_ID=7Yd4fxojkMc9ZvCiewx7coorSnFm84VccBiNxX3hujUH

Constants Configuration

Key constants can be modified in src/constants.rs:

// Minimum staking amount (10 USDC)
pub const MIN_STAKING_AMOUNT: u64 = 10_000_000;

// Initial credit score
pub const INITIAL_SCORE: u16 = 50;

// Grace period for late payments
pub const GRACE_PERIOD_DAYS: u8 = 15;

🛣️ Roadmap

Phase 1: Core Protocol ✅

• Staking mechanism
• BNPL contracts
• Credit scoring
• Whitelist system

Phase 2: Enhanced Features 🔄

• Card system implementation
• NFT utility integration
• FlexYield mechanism
• Cross-chain bridges

Phase 3: Advanced Features 🔜

• FlexBoost merchant integration
• Mobile SDK
• DeFi integrations
• Governance token

🔒 Security

Audits

• Code audit by Certik
• Economic audit by Gauntlet
• Bug bounty program

Best Practices

• All functions require appropriate signatures
• Critical operations include checks and balances
• Automatic liquidation prevents bad debt
• Comprehensive testing coverage

🤝 Contributing

We welcome contributions! Please see our Contributing Guide for details.

Development Flow

1. Fork the repository
2. Create a feature branch
3. Write tests for new functionality
4. Ensure all tests pass
5. Submit a pull request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🔗 Links

• Website: flex-fi.io
• Documentation: docs.flex-fi.io
• Twitter: @FlexFi_
• Discord: FlexFi Community

🏆 Key Achievements

• ✅ Successful Staking: 100 USDC staked ✓
• ✅ Score System: 50 initial points ✓
• ✅ Whitelist Integration: Secure access control ✓
• ✅ Automated Testing: Comprehensive test suite ✓

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Built with ❤️ on Solana

FlexFi: Redefining the future of payments with crypto-backed credit.