Senior Java Full Stack Developer - Payments Expert

TECH AALTO PTE. LTD.; Singapore; On-site; SGD 180,000 - 240,000; Full time

Job summary

Tech Aalto Pte Ltd in Singapore is seeking a Senior Java Full Stack Developer with 8+ years of experience in software development and hands-on payments domain expertise. You will design and build secure, scalable payment applications across backend services and frontend interfaces, guiding architectural decisions and engineering practices.

You will lead development of REST APIs, microservices, and integrate with payment gateways while upholding security and performance.

Qualifications

• 8+ years of professional software development experience.
• Experience with Java, Spring Boot, and backend technologies.
• Frontend experience with JavaScript/TypeScript and Angular/React.
• Experience designing REST APIs and building microservices.
• Significant payments domain experience including payment processing or integrations.
• Knowledge of payment workflows such as authorization, capture, refunds, settlement, and reconciliation.
• Experience with relational databases such as PostgreSQL, MySQL, or Oracle.
• Familiarity with messaging systems such as Kafka or RabbitMQ.
• Experience with Git, automated testing, and CI/CD pipelines.
• Strong understanding of application security, authentication, authorization, and data protection.

Responsibilities

• Lead the design, development, testing, and maintenance of full-stack applications using Java and modern frontend technologies.
• Build scalable backend services and REST APIs for payment processing, transaction management, and related workflows.
• Develop responsive user interfaces and integrate them with backend services.
• Design and support payment flows, including authorization, capture, refunds, settlement, reconciliation, and transaction-status tracking.
• Integrate with payment gateways, processors, banks, and other third-party financial services.
• Apply secure coding practices and support compliance with relevant payment-security requirements.
• Identify and resolve production issues; improve application performance, reliability, and scalability.
• Write and review unit, integration, and automated tests.
• Participate in architecture and design discussions, code reviews, and technical planning.
• Mentor developers and collaborate with product, QA, design, and other engineering teams.

Skills

Full-stack development

REST API design

Security best practices

Tools

Java

Spring Boot

JavaScript/TypeScript

Angular

React

Microservices

PostgreSQL

MySQL

Oracle

Kafka

RabbitMQ

Git

CI/CD

Security practices

Job description

Tech Aalto Pte Ltd in Singapore is seeking a Senior Java Full Stack Developer with 8+ years of experience in software development and hands-on payments domain expertise. You will design and build secure, scalable payment applications across backend services and frontend interfaces, guiding architectural decisions and engineering practices.

You will lead development of REST APIs, microservices, and integrate with payment gateways while upholding security and performance.