FULLSTACK DASHBOARD: Architecture & Implementation

FRONTEND STACK
• Framework: React 18 with TypeScript
• State: Zustand (lightweight, no boilerplate)
• Real-time: WebSocket via Socket.io (subscriptions on mount)
• Styling: Tailwind + Headless UI (accessible components)
• Deployment: Vercel (auto-deploy on push)

UI COMPONENTS
• Header: Company logo, user menu, settings link (sticky)
• Left sidebar: Nav links (Dashboard, Orders, Analytics, Settings)
• Main content:
  → Cards: Total revenue (MTD), active customers, avg order value, churn rate
  → Charts: Revenue trend (30 days), customer lifecycle (cohort), order volume
  → Notifications badge: Unread alerts (red dot if count > 0)
• Real-time notification panel: Slide-in drawer, dismissable notifications

BACKEND STACK
• Framework: Node.js + Express (or Fastify for speed)
• Database: PostgreSQL (customers, orders, notifications tables)
• Caching: Redis (user sessions, dashboard metrics cache, 5-min TTL)
• Real-time: Socket.io server, emit notifications on order/customer events
• Auth: JWT tokens, refresh token rotation every 30 days

API ENDPOINTS
• GET /api/dashboard/summary → {revenue, customers, avg_order_value, churn}
• GET /api/dashboard/revenue-trend?days=30 → [{date, revenue}]
• GET /api/dashboard/notifications?limit=20 → [{id, type, message, timestamp}]
• PATCH /api/notifications/{id}/read → mark as read
• WebSocket /socket.io → subscribe to events (order, customer, alert)

DATABASE SCHEMA
• Table: customers (id, name, email, created_at, churn_date)
• Table: orders (id, customer_id, amount, created_at, status)
• Table: notifications (id, user_id, type, message, read_at, created_at)
• Indexes: customer_id on orders (for query speed), created_at on orders (trend queries)

REAL-TIME FLOW
1. Order created in DB → trigger function fires
2. Backend queries updated metrics (total revenue, customer count)
3. Metrics cached in Redis (refresh every 5 min)
4. Socket.io emits {type: 'order_created', data: {...}} to all connected clients
5. React component receives event, updates state, user sees notification + updated card values

DEPLOYMENT
• Frontend: Vercel (auto-deploy on git push)
• Backend: AWS EC2 or Heroku (Node app + PostgreSQL)
• Database: AWS RDS PostgreSQL (multi-AZ for reliability)
• Monitoring: Sentry for errors, CloudWatch for logs

PERFORMANCE TARGETS
• Page load: <2 seconds (metrics cached)
• Notification latency: <1 second (Socket.io)
• Dashboard updates: Real-time (WebSocket push)

SECURITY
• Auth: JWT, httpOnly cookies (prevent XSS)
• Rate limiting: 100 requests/minute per user
• CORS: Whitelist vercel.app domain only
• SQL injection: Use parameterized queries