GCX International Trading Platform

Full-Stack Platform Rebuild

Overview

This international trading platform facilitates B2B2C transactions across multiple jurisdictions. I led the complete rebuild of the platform, redesigning the database architecture, API layer, and React frontend to support complex multi-currency operations while maintaining regulatory compliance.

The Challenge

The existing platform had accumulated significant technical debt:

• Monolithic codebase with tightly coupled components
• Database design that couldn't scale with transaction volume
• No clear separation between B2B and B2C workflows
• Compliance tracking scattered across multiple systems

Database Architecture

The rebuild centered on a properly normalized relational schema:

Scale

• 52 tables covering entities, transactions, inventory, and compliance
• 77 foreign key relationships ensuring referential integrity
• 3.7M+ rows in production with optimized query patterns

Core Entities

Organizations ──┬── Users ──── Permissions
                │
                ├── Products ── Inventory
                │
                └── Transactions ── Line Items
                                      │
                                      └── Compliance Records

Key Design Decisions

Multi-Currency Support

• Separate currency and exchange rate tables
• Transaction amounts stored in both local and base currency
• Audit trail for all currency conversions

Regulatory Compliance

• Every transaction linked to compliance checkpoint records
• Document storage with version history
• Automated reporting exports per jurisdiction

API Architecture

Node.js/TypeScript backend with RESTful design:

Authentication & Authorization

• JWT-based authentication
• Role-based access control (RBAC)
• Organization-level data isolation

Transaction Processing

• Atomic operations for multi-step transactions
• Optimistic locking for inventory management
• Event sourcing for audit trail

Frontend Architecture

React frontend with complex state management:

Multi-View Filtering

• Saved filter presets per user
• Real-time inventory availability
• Bulk operations support

Responsive Dashboard

• Key metrics visualization
• Transaction timeline
• Compliance status indicators

Technical Highlights

Performance Optimization

• Query optimization reducing average response time by 60%
• Pagination and lazy loading for large datasets
• Connection pooling for database efficiency

Developer Experience

• TypeScript throughout the stack
• Generated API documentation
• Comprehensive integration test suite

Results

The rebuilt platform successfully supports:

• Active trading operations across multiple countries
• Thousands of transactions processed monthly
• Full regulatory audit capabilities
• Sub-second response times for complex queries

This project demonstrates full-stack architectural thinking, complex relational database design, and building systems that operate in heavily regulated industries.