International Money Transfer Platform

Project Overview

Led the development of a B2C fintech platform that enables users to send money internationally using Solana blockchain technology. The platform provides a secure, escrow-based transfer system that ensures funds are protected throughout the transaction lifecycle.

The application features a modern Next.js frontend, robust backend services built with Fastify, and sophisticated workflow orchestration using Temporal.io to handle the complexities of blockchain-based financial transactions.

Technical Architecture

The platform is built as an Nx monorepo containing multiple interconnected packages:

Frontend Application: Next.js 13+ with React 18, Tailwind CSS, and a custom component library built with Radix UI primitives. The UI features real-time transaction status updates via Ably WebSocket integration and map visualizations using Deck.gl.

Backend Services: TypeScript microservices built with Fastify, handling user management, payment processing, escrow operations, and referral systems. Services communicate through well-defined APIs with comprehensive OpenTelemetry tracing for observability.

Workflow Orchestration: Temporal.io handles complex, long-running business processes with built-in retry logic and error recovery. The escrow transfer workflow manages the complete transaction lifecycle from creation through completion or cancellation.

Blockchain Integration: Direct integration with Solana using the Web3.js SDK and Anchor framework. Custom escrow program handles secure fund locking, release, and cancellation with authority-based transaction signing.

Key Contributions

Platform Architecture & Leadership

Led the architecture and implementation of the full-stack fintech platform from the ground up:

• Designed the overall system architecture using Nx monorepo with shared packages across web app, services, and workers
• Managed 7,900+ lines of TypeScript backend services
• Built 37+ React components for the web application

Workflow Orchestration

Designed and built Temporal.io workflow orchestration for complex financial transactions:

• Implemented resilient workflow patterns for multi-step blockchain operations
• Built retry logic and error recovery for non-deterministic blockchain operations
• Created compensation logic for transaction rollbacks

Blockchain Integration

Integrated Solana blockchain for secure escrow-based transfers:

• Developed escrow smart contract integration using Web3.js SDK and Anchor framework
• Built synchronization between on-chain state and off-chain database records
• Implemented authority-based transaction signing for secure fund operations

State Machine Design

Implemented comprehensive state machine for transfer lifecycle management:

• Used XState finite state machines for deterministic state management
• Managed complex state transitions across the full escrow lifecycle
• Ensured consistency between frontend and backend state representations

Key Features

Escrow-Based Transfers

Implemented a secure escrow system where funds are locked on-chain until the recipient claims them. The workflow handles transaction creation, confirmation tracking, claim processing, and expiration with full state machine management via XState.

Real-Time Updates

Integrated Ably for real-time messaging, enabling instant status updates across the platform. Users see transaction progress in real-time without polling.

Resilient Transaction Processing

Temporal workflows ensure that complex multi-step operations complete reliably, with automatic retry handling for transient failures and proper compensation logic for rollbacks.

Technologies

The project showcases modern full-stack development with TypeScript end-to-end, from React components through backend services to blockchain interactions. Key infrastructure includes Supabase (PostgreSQL), distributed tracing with OpenTelemetry, and error monitoring via Sentry.