Full-Stack Software Engineer (Fintech / Digital Assets)

United States Digital Space LLC; Singapore; On-site; SGD 60,000 - 90,000; Full time

Job summary

United States Digital Space LLC is seeking a capable full-stack engineer to design and build high-performance backend services and a responsive React SPA for trading, KYC, and financial workflows. You will integrate frontend with robust REST APIs, manage authentication flows, and apply AI-assisted coding to accelerate delivery.

The role requires 2+ years of full-stack experience with Django/FastAPI/Flask, Django REST Framework, React, and database tuning across MySQL/PostgreSQL and NoSQL stores.

Qualifications

• Bachelor's degree in Computer Science or a related field.
• Minimum 2 years of full-stack development experience; strong command of Django / FastAPI / Flask, proficient with Django REST Framework and API design.
• Strong React frontend skills: JavaScript (ES6+) / JSX, function components + Hooks, React Router; solid component-based architecture.
• Familiar with React state management (Context API + Hooks); comfortable with Vite, pnpm, ESLint.
• Proficient in HTML/CSS, responsive design, API integration, authentication (JWT / 2FA) and CORS in a decoupled architecture.
• Proficient in AI-assisted engineering: using Codex and Claude Code to support the SDLC.
• Solid grasp of multithreading/async programming for high-concurrency scenarios.
• Hands-on experience with message queues (Kafka, RabbitMQ, Redis Pub/Sub).
• Strong relational databases (MySQL, PostgreSQL) and NoSQL stores (MongoDB, Redis) with performance tuning.
• Familiar with Linux and basic deployment/automation; experience with banking or crypto integrations is a plus.
• Proven analytical/problem-solving skills and good teamwork/communication.
• Mandarin proficiency is preferred for collaboration.

Responsibilities

• Design and develop high-performance backend services and stable RESTful APIs in a decoupled architecture.
• Build services with Django / FastAPI / Flask and Django REST Framework for business APIs.
• Develop and maintain a React + Vite SPA for trading, KYC/onboarding, fiat, settlement, and accounts.
• Integrate frontend with backend APIs, handle JWT/2FA, validation, reCAPTCHA, and e-sign flows.
• Leverage AI-assisted coding tools to improve velocity, quality, and delivery speed.
• Implement and optimise multithreading/async processing for high concurrency.
• Use Kafka, RabbitMQ, or Redis Pub/Sub for messaging and async tasks.
• Contribute to database design/optimisation (MySQL/PostgreSQL/MongoDB/Redis).
• Collaborate with product/design/QA from design to delivery and continuous improvement.
• Write quality code and tests; participate in code reviews; support deployment and monitoring (GCP)
• Uphold security and data compliance in a regulated financial context.

Skills

Full-stack development

Django / FastAPI / Flask

Django REST Framework

React (ES6+)

React Hooks

REST API design

JWT / 2FA authentication

Database design (MySQL/PostgreSQL)

NoSQL (MongoDB/Redis)

Web security

Education

Bachelor's degree in Computer Science or related field

Tools

Kafka

RabbitMQ

Redis Pub/Sub

Job description

Responsibilities

• Design and develop high-performance, highly available backend services and stable, scalable RESTful APIs (decoupled frontend/backend architecture)


• Build services with Django / FastAPI / Flask, using Django REST Framework for business APIs


• Develop and maintain our React + Vite single-page application covering trading, KYC/onboarding, fiat deposit/withdrawal, settlement, and account modules, with responsive support for desktop and mobile


• Integrate frontend with backend REST APIs, handling JWT / 2FA authentication, form validation, reCAPTCHA, and e-signature flows


• Use AI coding assistants like Codex and Claude Code proficiently across the software development lifecycle — from feature implementation to debugging, testing, and code review — to raise development velocity, code quality, and delivery speed


• Implement and optimise multithreaded / asynchronous processing for task scheduling and data flows under high concurrency


• Use Kafka, RabbitMQ, or Redis Pub/Sub for inter-service messaging and asynchronous task processing


• Contribute to database design and optimisation across MySQL / PostgreSQL / MongoDB / Redis (partitioning, index tuning)


• Collaborate closely with product, design, and QA from design through delivery and continuous improvement


• Write high-quality code and unit tests; participate in code reviews to safeguard stability and maintainability


• Work comfortably in Linux server environments; support automated deployment, performance monitoring, and troubleshooting (GCP / cloud experience preferred)


• Uphold security and data compliance in a regulated financial context: field-level encryption, access control, and audit logging across data transmission, storage, and processing

Requirements

• Bachelor's degree or above in Computer Science or a related field, with solid fundamentals (data structures, algorithms, operating systems, networking)


• Minimum 2 years of full-stack development experience; strong command of at least one of Django / FastAPI / Flask, proficient with Django REST Framework, and able to independently design RESTful APIs


• Strong React frontend skills: proficient in JavaScript (ES6+) / JSX, React function components + Hooks, React Router; solid grasp of component-based architecture and frontend engineering practices


• Familiar with React state management (Context API + custom Hooks); comfortable with Vite builds, pnpm, and writing clean, maintainable code (ESLint)


• Proficient in HTML / CSS, able to hand-write responsive styles with mobile adaptation; familiar with API integration, authentication (JWT / 2FA), and CORS handling in a decoupled architecture


• Proficient in AI-assisted engineering: skilled at using AI coding assistants like Codex and Claude Code to support the full development lifecycle — requirements implementation, debugging, testing, and code review


• Solid grasp of multithreading and coroutine / async programming for high-concurrency scenarios


• Hands-on project experience with message queues (Kafka, RabbitMQ, Redis Pub/Sub)


• Strong command of relational databases (MySQL, PostgreSQL) and NoSQL stores (MongoDB, Redis), including performance tuning


• Familiar with Linux; basic deployment, operations, and automation scripting skills


• Experience integrating with banking systems, third-party payment platforms, or crypto exchanges is a plus


• Strong independent analytical and problem-solving skills; good teamwork and communication


• Proficiency in Mandarin is preferred, as the role involves collaborating with Mandarin-speaking team members and counterparts

Bonus

• Project experience in payments, asset management, wallet systems, or risk/compliance systems


• Familiarity with the cryptocurrency industry, Web3, or blockchain technologies


• Familiarity with financial interface standards (payment protocols, clearing and settlement flows) and compliance processes such as KYC/AML screening, transaction monitoring, and Travel Rule workflows


• Experience with data encryption, permission management, and audit logging


• Deep hands-on experience with AI-assisted development and agent engineering — building or optimising AI coding workflows and harnesses within the SDLC


• Frontend data visualisation / charting (market data, reports), i18n, and performance optimisation


• TypeScript; familiarity with GCP services (Cloud SQL, GCS, Cloud Run, Cloud Tasks, Secret Manager)


• Prior experience working in a regulated financial services environment