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Senior Java Backend Developer

Summary

Build and maintain high-volume transaction systems and APIs for an international payment gateway using Java, Spring Boot, and microservices.

Responsibilities

  • Design, develop, and maintain scalable backend systems for high-volume transaction processing and international payment gateway integrations.
  • Develop secure and high-performance APIs for internal and external system integration.
  • Write clean, maintainable, and testable code following engineering best practices.
  • Contribute to architecture design for scalable, resilient, and fault‑tolerant systems.
  • Implement event‑driven and asynchronous processing for backend services.
  • Support integration across multiple internal and external platforms.
  • Design and implement message‑driven architectures using enterprise messaging systems.
  • Optimize application, database, and service‑level performance.
  • Perform load testing and identify system bottlenecks.
  • Troubleshoot production issues and perform root cause analysis (RCA).
  • Ensure system stability and reliability in high‑throughput environments.
  • Work closely with DevOps teams to support CI/CD pipeline implementation.
  • Manage build, deployment, and release processes across environments.

Requirements

  • Bachelor’s degree in Computer Science, Software Engineering, or a related field.
  • 6–9 years of experience in Java backend development.
  • Strong proficiency in Java 8+ (preferably Java 21) and Spring Boot.
  • Proven experience with microservices architecture, event‑driven architecture, and REST API development.
  • Hands‑on experience with messaging systems, preferably Solace.
  • Strong experience with MySQL, including database tuning, SQL optimization, indexing, and query tuning.
  • Experience with unit testing frameworks such as JUnit and Mockito.
  • Proficiency in Maven, Git, Jira, and Jenkins‑based CI/CD pipelines.
  • Experience in load testing, performance testing, and backend optimization.
  • Strong troubleshooting and debugging capabilities, including production issue resolution and root cause analysis.
  • Proven experience in e‑commerce, banking, or other high‑volume transaction environments.
  • Strong experience building distributed, scalable, and high‑availability systems.
  • Hands‑on experience implementing microservices and event‑driven architecture in production environments.
  • Experience handling performance‑critical and real‑time backend systems.
  • Demonstrated ability to work in production support and critical incident resolution environments.

Network for Electronic Transfers (Singapore) Pte Ltd.

See also