Senior JAVA Full Stack Developer - Payment

Singapore (Singapore)

Senior JAVA Full Stack Developer - Payment

Role overview

We’re seeking a Senior Java Full Stack Developer with 8+ years of software development experience, including hands-on experience in the payments domain. You’ll design and build secure, scalable payment applications across backend services and frontend interfaces, and help guide technical decisions and engineering practices.

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.

Required qualifications

• 8+ years of professional software development experience, including full-stack application development.
• Strong experience with Java, Spring Boot, and related backend technologies.
• Hands-on frontend experience with JavaScript or TypeScript and Angular or React.
• Experience designing and consuming REST APIs and building microservices.
• Significant experience in the payments domain, including payment processing or payment-system 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 platforms such as Kafka or RabbitMQ.
• Experience with Git, automated testing, and build tools.
• Strong understanding of application security, authentication, authorization, and data protection.

Preferred qualifications

• Experience with AWS, Azure, or Google Cloud.
• Familiarity with Docker, Kubernetes, and CI/CD pipelines.
• Knowledge of PCI DSS and payment-security practices.
• Experience with distributed systems, idempotency, retries, and transaction consistency.
• Familiarity with observability tools for logging, metrics, and tracing.
• Prior experience mentoring developers or contributing to technical direction.

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