🪺 PayNest — Full-Stack Payment Web Application

A secure, scalable payment web application built with React.js, Node.js, Express.js, and MongoDB.

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🚀 Tech Stack

Layer	Tech
Frontend	React.js, React Router v6, Axios, Lucide
Styling	Custom CSS (PayPal-inspired design system)
Backend	Node.js, Express.js
Database	MongoDB + Mongoose
Auth	JWT (jsonwebtoken) + bcryptjs

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📁 Project Structure

paynest/
├── backend/
│   ├── models/
│   │   ├── User.js           # User schema (balance, accountId, bcrypt)
│   │   └── Transaction.js    # Transaction schema (send/receive)
│   ├── routes/
│   │   ├── auth.js           # POST /register, POST /login
│   │   ├── user.js           # GET /me, GET /search
│   │   └── transaction.js    # POST /send, GET /history, GET /stats
│   ├── middleware/
│   │   └── auth.js           # JWT verification middleware
│   ├── server.js
│   ├── .env
│   └── package.json
└── frontend/
    ├── src/
    │   ├── context/
    │   │   └── AuthContext.js   # Global auth state + API calls
    │   ├── pages/
    │   │   ├── Login.js         # Login page
    │   │   ├── Register.js      # Register page
    │   │   ├── Dashboard.js     # Balance, stats, recent activity
    │   │   ├── Send.js          # Send money with user search + confirm modal
    │   │   ├── History.js       # Paginated transaction history with filters
    │   │   └── Profile.js       # User profile and security info
    │   ├── components/
    │   │   └── Layout.js        # Sidebar + navigation
    │   ├── App.js               # Routes (public + private)
    │   ├── index.css            # Complete design system
    │   └── index.js
    └── package.json

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⚙️ Setup & Run

1. Prerequisites

• Node.js 18+
• MongoDB running locally OR a MongoDB Atlas URI

2. Backend Setup

cd backend
npm install
# Edit .env if needed (MONGO_URI, JWT_SECRET)
npm run dev       # nodemon for dev
# OR
npm start         # production

3. Frontend Setup

cd frontend
npm install
npm start         # Runs on http://localhost:3000

Backend runs on port 5000, Frontend on port 3000. The frontend proxies /api → http://localhost:5000 via package.json.

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🔐 Features

Authentication

• JWT-based login/register
• Passwords hashed with bcryptjs (10 rounds)
• 7-day token expiry
• Protected routes on frontend and backend

Dashboard

• Live balance display
• Stats: total sent, total received, transaction count
• Recent activity feed

Send Money

• Real-time user search by email
• Amount validation against balance
• Confirm modal before transfer
• Atomic MongoDB transactions (sender debit + receiver credit)
• Success/failure feedback

Transaction History

• Paginated (10 per page)
• Filter by All / Sent / Received
• Full counterpart info + timestamps + notes

Profile

• Account ID, email, join date
• Balance snapshot
• Security info (JWT, session status)

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🗃️ API Endpoints

Method	Endpoint	Auth	Description
POST	/api/auth/register	❌	Register new user
POST	/api/auth/login	❌	Login, get JWT
GET	/api/user/me	✅	Get profile
GET	/api/user/search?q=email	✅	Search users
POST	/api/transaction/send	✅	Send money
GET	/api/transaction/history	✅	Paginated history
GET	/api/transaction/stats	✅	Sent/received totals

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🌱 Demo

• New users start with ₹1,000.00 demo balance
• All transfers are atomic (MongoDB sessions)
• Try registering 2 accounts and sending between them!