🚀 Nexus Tech Titans — Credence

📌 Overview

This project is a full-stack system designed to evaluate and verify user activities for creditworthiness using:

• 🧠 AI-based document verification (Gemini Vision)
• 🔗 Blockchain for tamper-proof records
• 🗄 MongoDB Atlas for data storage
• 🌐 React frontend + FastAPI backend

The system has 3 roles:

• 👤 User → Uploads activities & documents
• 🕵️ Verifier → Validates authenticity (AI + manual)
• 💰 Lender → Uses verified data for decision-making

---

⚙️ Tech Stack

Backend

• FastAPI
• MongoDB Atlas
• Gemini API (Vision)
• Web3 / Hardhat (Blockchain)

Frontend

• React + TypeScript + Vite

Blockchain

• Solidity
• Hardhat (local node)

---

🧠 System Flow

1. User uploads activity + documents

2. Files stored locally (/uploads)

3. Activity stored in MongoDB

4. Verifier:

   • Fetches pending activities
   • AI checks document authenticity
   • Approves / rejects

5. Hash stored on blockchain for integrity

---

🛠️ How to Run the Project

🔹 1. Clone Repository

git clone https://github.com/NEXUS-2026/nexus_tech_titans.git
cd nexus_tech_titans

---

🔹 2. Backend Setup

cd backend
python -m venv venv

Activate venv

Windows (Git Bash):

source venv/Scripts/activate

Windows (CMD):

venv\Scripts\activate

---

Install dependencies

pip install -r requirements.txt

---

🔹 3. Setup Environment Variables

Create .env inside backend/:

MONGO_URL=your_mongodb_atlas_connection_string
GEMINI_API_KEY=your_gemini_api_key

⚠️ DO NOT push .env to GitHub

---

🔹 4. Run Backend

uvicorn main:app --reload

👉 Runs on: http://127.0.0.1:8000

Swagger Docs: http://127.0.0.1:8000/docs

---

🔹 5. Blockchain Setup

Open new terminal:

cd Documents/nexus/blockchain
npm install

Start local blockchain:

npx hardhat node

---

Deploy contract (new terminal):

npx hardhat run scripts/deployLoanManager.js --network localhost

👉 Copy deployed contract address into .env if required

---

🔹 6. Frontend Setup

cd frontend
npm install
npm run dev

👉 Runs on: http://localhost:5173

---

📂 Project Structure

backend/
  routes/
  services/
  models/
  uploads/       # local file storage
  main.py

frontend/
  src/

Documents/nexus/blockchain/
  contracts/
  scripts/

---

🔥 Key Features

• ✅ Multi-role system (User / Verifier / Lender)
• ✅ AI-based document validation (Gemini Vision)
• ✅ Fraud detection logic based on activity patterns
• ✅ Blockchain-based verification storage (tamper-proof)
• ✅ File upload with multi-document support
• ✅ MongoDB Atlas integration
• ✅ Psychometric-based baseline scoring using structured user questionnaires
• ✅ Dynamic trust score updated based on verification outcomes and behavioral inputs

---

⚠️ Important Notes

• Files are currently stored locally (/uploads)
• MongoDB stores only file paths, not files
• For production → migrate to cloud storage (S3 / Firebase)

---

🚧 Known Limitations

• Local file storage (not scalable)
• Basic AI validation (not fine-tuned)
• Hardhat runs on local network only

---

👨‍💻 Contributors

• Backend, AI, Blockchain, Frontend team (Nexus Tech Titans)

---

💡 Future Improvements

• Cloud storage integration (Firebase/S3)
• Advanced AI fraud detection
• Deployment (Docker + Cloud)
• Real blockchain network integration

---

⭐ Final Note

This project demonstrates:

• Full-stack integration
• AI + Blockchain synergy
• Real-world fintech problem solving