Complete POS System with Supabase Integration

We're looking for an experienced developer to complete our Point of Sale (POS) system with Supabase integration. The project is built using React, TypeScript, and Supabase as the backend database service.

Current System State
Our POS system currently has:

Frontend built with React and TypeScript
UI components using Shadcn UI library
Partial Supabase integration for data storage
Basic sales, inventory, and supplier management functionality
User authentication and role-based access
Required Tasks
Complete Supabase Database Integration
Standardize database schema across all modules
Implement proper table relationships and constraints
Set up Row Level Security (RLS) policies
Create database initialization scripts
Enhance POS Sales Functionality
Complete the sales submission process
Implement real-time inventory updates when sales occur
Add comprehensive payment processing (cash, card, UPI, device exchange)
Integrate device exchange functionality with proper valuation
Inventory Management
Complete inventory tracking system with real-time updates
Implement IMEI/serial number tracking for devices
Add low stock alerts and inventory reporting
Connect inventory with supplier bills and sales
Reporting and Analytics
Create sales reports with filtering options
Implement inventory valuation reports
Add supplier payment tracking and reporting
Create dashboard with key performance indicators
Technical Requirements
Languages/Frameworks: React, TypeScript, Node.js
Database: Supabase (PostgreSQL)
State Management: React Context API and custom hooks
UI Components: Shadcn UI, Tailwind CSS
Authentication: Supabase Auth
Deployment: Vercel or similar platform
Required Skills
Strong experience with React and TypeScript
Experience with Supabase or PostgreSQL
Knowledge of database design and optimization
Understanding of retail/POS business processes
Experience with real-time data synchronization
Ability to implement responsive UI designs