QuickCash: A Full-Stack Peer-to-Peer Payments Application

A secure and robust full-stack web application that simulates a peer-to-peer (P2P) payment system, allowing users to create accounts, manage their wallets, and transfer funds to other users instantly.

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🚀 Overview

This project is a complete MERN-stack implementation of a digital wallet application. It provides a seamless user experience for signing up, logging in, checking account balances, and performing secure transactions. The primary focus was on ensuring transactional integrity and data security, which are paramount in any financial application.

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✨ Key Features

• Secure User Authentication: Robust user sign-up and sign-in functionality with password hashing using bcrypt and session management via JSON Web Tokens (JWT).
• Account Management: Users get a dedicated wallet upon registration with a randomly assigned starting balance.
• Real-time User Search: Instantly find and filter other users on the platform to initiate a transfer.
• ACID-Compliant Transactions: Core fund transfer logic is built using Mongoose sessions to ensure atomic, consistent, isolated, and durable (ACID) transactions, preventing data corruption and loss of funds.
• Dynamic & Responsive UI: A clean, modern, and intuitive user interface built with React and styled with Tailwind CSS for a seamless experience on all devices.
• RESTful API: A well-structured and documented backend API to handle all application logic.

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🛠️ Tech Stack

Category	Technology
Frontend	React.js, React Router, Axios, Tailwind CSS
Backend	Node.js, Express.js
Database	MongoDB, Mongoose
Security	JSON Web Tokens (JWT), bcrypt
Validation	Zod

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⚙️ Getting Started

To get a local copy up and running, follow these simple steps.

Prerequisites

• Node.js and npm (or yarn) installed
• MongoDB installed and running, or a MongoDB Atlas connection string

Installation & Setup

1. Clone the repository:

   git clone [https://github.com/your-username/your-repo-name.git](https://github.com/your-username/your-repo-name.git)
   cd your-repo-name

2. Backend Setup:

   # Navigate to the backend directory
   cd backend
   
   # Install NPM packages
   npm install
   
   # Create a .env file in the /backend directory and add the following variables
   # MONGO_URL=your_mongodb_connection_string
   # JWT_SECRET=your_jwt_secret_key
   # PORT=3000
   
   # Start the backend server
   npm start

3. Frontend Setup:

   # Navigate to the frontend directory from the root
   cd frontend
   
   # Install NPM packages
   npm install
   
   # Create a .env file in the /frontend directory and add the following variable
   # VITE_SERVER_URL=http://localhost:3000
   
   # Start the frontend development server
   npm run dev

The application should now be running on http://localhost:5173 (or another port specified by Vite).

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📄 License

Distributed under the MIT License. See LICENSE for more information.