E-Commerce Platform

A modern, scalable e-commerce platform built from scratch with performance and user experience as top priorities.

Overview

Built a complete e-commerce solution for a mid-sized retail company looking to expand online. The platform handles everything from product catalog management to payment processing and order fulfillment.

Key Features

Customer-Facing

• Product Catalog - Dynamic filtering, sorting, and search with instant results
• Shopping Cart - Real-time inventory checking and price calculations
• Checkout - Secure payment processing via Stripe with Apple Pay/Google Pay support
• Order Tracking - Real-time order status updates with email notifications
• User Accounts - Profile management, order history, and saved addresses

Admin Dashboard

• Inventory Management - Real-time stock tracking and low-stock alerts
• Order Management - Bulk order processing and fulfillment workflow
• Analytics - Sales dashboards, customer insights, and revenue reporting
• Product Management - Easy product creation with image uploads and variants

Technical Highlights

Performance Optimization

• Implemented Redis caching reducing database queries by 70%
• Optimized images with WebP format and lazy loading
• Server-side rendering for critical pages improving SEO and load times
• CDN integration for global content delivery

Scalability

• Microservices architecture allowing independent scaling
• Horizontal scaling with load balancing
• Database read replicas for improved query performance
• Message queues for async processing (order emails, inventory updates)

Security

• JWT authentication with refresh tokens
• Rate limiting to prevent abuse
• Input validation and sanitization
• PCI-compliant payment processing via Stripe

Architecture

┌─────────────┐     ┌──────────────┐     ┌─────────────┐
│  React SPA  │────▶│   REST API   │────▶│ PostgreSQL  │
└─────────────┘     │  (Express)   │     └─────────────┘
                    └──────┬───────┘
                           │
                    ┌──────▼───────┐
                    │    Redis     │
                    │   (Cache)    │
                    └──────────────┘

Challenges & Solutions

Challenge 1: Inventory Sync

Problem: Multiple users buying same product simultaneously causing overselling

Solution: Implemented optimistic locking with Redis to ensure inventory accuracy during concurrent purchases

Challenge 2: Payment Processing

Problem: Handling payment failures gracefully while maintaining order integrity

Solution: Built robust state machine for order processing with automatic retry logic and customer notifications

Challenge 3: Performance at Scale

Problem: Slow page loads during traffic spikes

Solution: Implemented multi-layer caching strategy (CDN, Redis, in-memory) and database query optimization

Results

• Performance: 60% faster page load times compared to previous platform
• Conversion: 25% increase in conversion rate due to improved UX
• Uptime: 99.9% uptime over 6 months in production
• Scale: Successfully handled Black Friday with 10k concurrent users
• Revenue: Processing over $50k in monthly transactions

Tech Stack Details

Frontend

• React 18 with TypeScript
• Tailwind CSS for styling
• React Query for data fetching
• React Hook Form for forms

Backend

• Node.js with Express
• PostgreSQL with Prisma ORM
• Redis for caching and sessions
• Bull for job queues

Infrastructure

• Docker containers
• AWS EC2 for hosting
• AWS S3 for image storage
• Cloudflare CDN
• GitHub Actions for CI/CD

Payment & Services

• Stripe for payments
• SendGrid for emails
• Sentry for error tracking

Future Improvements

• Mobile app (React Native)
• Multi-language support
• Wishlist and product recommendations
• Live chat support
• Advanced analytics dashboard

Screenshots

(Screenshots would go here in production)

Lessons Learned

1. Start with Performance: Built with performance in mind from day one rather than optimizing later
2. Testing Matters: Comprehensive test suite caught critical bugs before production
3. Monitor Everything: Proper logging and monitoring essential for maintaining uptime
4. User Feedback: Regular user testing revealed UX issues we wouldn’t have found otherwise

Project Status: ✅ Live in Production
GitHub: View Source Code
Demo: Try it Live