Java Software Engineer - Payment systems

Join a large-scale technology organization that powers payment and incentive platforms used across a diverse digital ecosystem. As a Software Engineer, you will contribute to the development, operation, and continuous improvement of secure, scalable, Java-based payment solutions.

Client Details

Our client is a leading technology and digital commerce organization with a large global ecosystem. The team develops payment and incentive platforms that support millions of users and focuses on security, scalability, and operational excellence.

Description

• Design, develop, test, and deploy Java-based payment applications and APIs
• Contribute to scalable and robust microservices architecture
• Develop and maintain secure RESTful APIs and third-party integrations
• Collaborate with engineers, product managers, and project managers to deliver business-critical solutions
• Participate throughout the full software development lifecycle, from requirements gathering to production support
• Analyze performance bottlenecks and implement optimization strategies
• Support architecture improvements focused on scalability and maintainability
• Create and maintain technical documentation
• Conduct and participate in code reviews while promoting engineering best practices
• Work with monitoring and distributed tracing tools to improve system observability
• Leverage AI-assisted development tools to improve productivity and development efficiency
• Contribute to continuous improvement initiatives across the engineering organization

Job Offer

• Opportunity to build and enhance large-scale payment platforms
• Exposure to high-traffic, security-focused systems
• Modern engineering environment utilizing microservices and cloud technologies
• Collaboration with international and cross-functional teams
• Opportunity to adopt and expand AI-assisted software development practices
• Stable long-term engagement with extension potential
• Tokyo-based position with standard business hours (9:00-17:30)
• Exposure to mission-critical products supporting a global digital ecosystem

To apply online please click the 'Apply' button below. For a confidential discussion about this role please contact Kayo Tojo +81366276145.

Required Qualifications

• Experience as a Software Engineer or similar role
• Strong proficiency in Java and SQL
• Hands-on experience with Spring Boot and Spring Framework
• Experience developing and maintaining RESTful APIs
• Experience designing and implementing microservices architectures
• Understanding of software design patterns, architecture principles, and development best practices
• Knowledge of Git or other version control systems
• Understanding of secure coding principles and application security
• Experience with performance tuning and optimization
• Experience working in Agile development environments
• Business-level English proficiency (equivalent to TOEIC 800+)

• Front-end development experience with HTML, CSS, and JavaScript
• Experience with AWS or other cloud platforms
• Experience with Docker and Kubernetes
• Knowledge of distributed tracing and monitoring solutions
• Experience with unit, integration, and performance testing frameworks
• Experience in e-commerce platforms or online transaction systems
• Experience using AI coding assistants such as GitHub Copilot or similar tools
• Contributions to open-source projects or participation in technical communities