Crypto Guardian

Crypto fraud detection app that analyzes wallet addresses for suspicious patterns and known scams.

⚠️ Note: Backend may take 10-30s on first request (Render free tier sleep mode).

Quick Start

pnpm install
pnpm dev

Access at:

• Frontend: http://localhost:5173
• Backend: http://localhost:3001

Setup

Prerequisites

• Node.js 24+ (use .nvmrc to set version: nvm use)
• pnpm 10.0.0+ (package manager specified in package.json)

1. Install dependencies:

   pnpm install

2. Environment configuration:

   Backend (.env):

   cp backend/.env.example backend/.env
   # Add Etherscan API key (free tier):
   # Sign up at https://etherscan.io/apis
   ETHERSCAN_API_KEY=your_key_here

   Frontend (.env):

   echo "VITE_API_URL=http://localhost:3001" > frontend/.env
   # For HTTPS during development (to avoid Chrome local network warnings):
   echo "VITE_API_URL=https://localhost:3001" > frontend/.env

3. Start development:

   pnpm dev              # Both services
   pnpm dev:frontend     # Frontend only (localhost:5173)
   pnpm dev:backend      # Backend only (localhost:3001)

Testing

• Manual API testing: node test-api.js
• Verify USD values display correctly in both API and frontend

Features

Security & Detection

• Multi-chain support (Ethereum, Bitcoin, BSC, Polygon, Arbitrum)
• Suspicious pattern detection
• Real-time address validation
• Risk scoring system (0-100)
• Transaction analysis
• USD value calculation (using CoinGecko API)
• Chrome security compliant (local network access handled)

Technical Stack

• Frontend: Vite + React + TypeScript + shadcn/ui + Tailwind CSS
• Backend: Node.js + Express + TypeScript
• API Integration: Etherscan, BlockCypher, and CoinGecko APIs

API

POST /api/check-address

Request:

{ "address": "0x742d35Cc6634C0532925a3b8D4C9db96C4b5Db45" }

Response:

{
  "verdict": "CLEAN",
  "risk_score": 15,
  "findings": [],
  "transaction_count": 24,
  "total_value": "$1,234.56",
  "recommendation": "Address appears to be safe"
}

License

MIT