Overview
POS/CRM System is an integrated retail management solution built for a fashion retail chain with 12 branches across Hanoi and Ho Chi Minh City. The system combines a Point of Sale (POS) terminal at each counter with a CRM for customer relationship management and a multi-branch inventory system — all in a single unified platform.
The key differentiator is the omnichannel design: online sales (website and mobile app) and offline sales (in-store POS) share the same data layer, allowing customers to buy online and return in-store — and vice versa — without friction.
The Challenge
The chain previously ran three disconnected systems: standalone POS software at each counter, a separate inventory management tool, and Excel for customer tracking. Unsynchronized data led to selling items not in stock, mis-applied promotions, and no ability to analyze overall customer purchase behavior.
The biggest technical challenge was handling concurrent transactions: when multiple branches simultaneously sell the last unit of a product, the system must guarantee no oversell occurs — even under high concurrency.
Our Solution
Ventra Rocket designed an event-driven architecture with PostgreSQL as the central data source. Every sale transaction is processed inside a database transaction with row-level locking to prevent concurrent oversell. Inventory updates propagate in real time to all POS terminals via WebSocket.
The CRM module builds a Customer 360 view: consolidating online and offline purchase history, loyalty points, product preferences, and automatic RFM (Recency, Frequency, Monetary) segmentation — enabling personalized, targeted marketing campaigns.
Key Features
- Unified Inventory Management: Inventory syncs in real time across all 12 branches — every sale anywhere updates stock immediately, with zero oversell guarantee.
- Smart POS Terminal: Touch-optimized interface for sales staff with fast product search, barcode scanning, automatic promotion application, and thermal receipt printing.
- Customer 360 CRM: Complete customer profiles with full purchase history, loyalty points, auto-generated RFM segments, and product recommendations based on past behavior.
- Promotion Engine: Flexible campaign builder — percentage discounts, buy-X-get-Y, time-limited flash sales, personalized vouchers — all auto-applied at checkout based on conditions.
- Real-time Revenue Dashboard: Revenue by branch, by staff member, and by product category with year-over-year comparison charts updated every minute.
Impact & Results
Six months after launch, conversion rate increased 40% thanks to promotions delivered to the right customers at the right time. Inventory discrepancy between system and physical count dropped from 3.2% to 0.1%. Checkout time per transaction decreased 35% due to the optimized POS flow.
The marketing team saves 20 hours per month through automated reporting. Customers are more satisfied with the flexible return policy and unified loyalty points across all channels.
Tech Stack Details
Laravel with Eloquent ORM and queue system handles complex business rules and background tasks (inventory sync, email sending, points calculation) reliably. Vue.js builds the POS terminal with offline support — staff continue selling during temporary internet outages, with data syncing automatically on reconnection. PostgreSQL with full ACID compliance guarantees absolute financial data integrity. Stripe handles international card payments with 3D Secure and webhook-based automatic refund processing.