Building a Modern Restaurant POS System from Scratch

A restaurant POS system is complex software that handles orders, payments, inventory, and customer management. Here's how to build one from scratch.

Core Features

Order Management

• Table layout visualization
• Menu item selection with modifiers
• Split bills and order splitting
• Order status tracking (pending, cooking, ready)

Payment Processing

• Multiple payment methods (cash, card, digital wallets)
• Tip handling
• Receipt generation
• Refund processing

Inventory Management

• Real-time stock tracking
• Low stock alerts
• Ingredient-level tracking
• Supplier management

Tech Stack Recommendation

// Frontend: React Native for cross-platform mobile
// Backend: Node.js with Express or Next.js API
// Database: PostgreSQL for relational data
// Real-time: Socket.io for live updates
// Payments: Stripe API

Database Schema

-- Tables schema
CREATE TABLE tables (
  id SERIAL PRIMARY KEY,
  number INTEGER NOT NULL,
  capacity INTEGER,
  status TEXT DEFAULT 'available'
);

CREATE TABLE orders (
  id SERIAL PRIMARY KEY,
  table_id INTEGER REFERENCES tables(id),
  status TEXT DEFAULT 'pending',
  created_at TIMESTAMP DEFAULT NOW()
);

CREATE TABLE order_items (
  id SERIAL PRIMARY KEY,
  order_id INTEGER REFERENCES orders(id),
  menu_item_id INTEGER REFERENCES menu_items(id),
  quantity INTEGER,
  price DECIMAL(10,2),
  status TEXT DEFAULT 'pending'
);

Key Implementation Tips

1. **Offline Mode**: Restaurants need functioning POS during internet outages
2. **Speed**: Every second counts - optimize for sub-second transactions
3. **Kitchen Display**: Sync orders to kitchen in real-time
4. **Reporting**: Daily, weekly, monthly sales and inventory reports

Conclusion

Building a restaurant POS requires understanding both technical and domain-specific challenges. Start with core ordering and expand from there.