Tools: Part 3: Final Architecture & Lessons Learned

1. The Big Picture: System Architecture ## 2. Performance Milestones ## 3. Key Lessons ## Final Thoughts The Opener Market project is finally coming to an end. In this final post, I will review the overall system architecture and share the key lessons learned from building a high-concurrency e-commerce platform. Our system is divided into three main domains, each solving a specific high-traffic problem: Building Opener Market was a deep dive into the world of scalable backend systems. This project taught me how to balance complex requirements with performance optimization. Templates let you quickly answer FAQs or store snippets for re-use. Are you sure you want to hide this comment? It will become hidden in your post, but will still be visible via the comment's permalink. Hide child comments as well For further actions, you may consider blocking this person and/or reporting abuse - Coupon Domain: Uses Redis Lua Scripts for atomic stock control and a Write-Back pattern to ensure data consistency without slowing down the user. - Order Domain: Implements Database Locking (Pessimistic/Optimistic) to prevent over-selling and ensure transaction integrity. - Search Domain: Powered by QueryDSL for type-safe dynamic queries and optimized with composite indexes for sub-second latency. - Search Latency: Reduced from 1.8s to 0.5s (72% improvement). - Throughput: Successfully handled high-concurrency coupon issuance using Redis memory instead of DB locks. - Consistency: Guaranteed atomic transactions across Balance, Stock, and Points. - Memory-First Strategy: For high-traffic events, the Database should be the last resort. Redis is essential for protecting the core system. - Asynchronous Processing: Decoupling the user response from heavy tasks (like DB persistence) is the secret to a smooth UX. - Data Integrity vs. Speed: In e-commerce, speed is important, but accuracy is everything. Always use @Transactional and proper locking strategies.