Haken Backend Software Engineer - Golang - Java Tokyo

Join one of Japan's leading internet and digital services groups as a Backend Software Engineer, building secure and scalable backend systems that help detect and prevent real-time fraud across high-volume global platforms.

You will design, develop, maintain, and optimise backend microservices and distributed systems using technologies such as Golang and Java. Working within an international engineering environment, you will help ensure that critical transaction systems remain secure, reliable, scalable, and highly available.

This is an excellent opportunity for a mid-level backend engineer who wants to strengthen their experience in Golang, Java, Kubernetes, Docker, microservices, cloud technologies, and fraud prevention systems while solving engineering challenges that directly protect millions of users.

This position is open to candidates currently residing in Japan.

Key Responsibilities

• Design, develop, maintain, and optimise secure backend applications and microservices within a distributed systems architecture.
• Build scalable backend services supporting high-volume, real-time transaction and fraud prevention platforms.
• Handle software development activities across coding, testing, maintenance, bug fixing, and continuous enhancement.
• Write clean, secure, reusable, and maintainable code that meets established engineering standards.
• Create and maintain clear technical documentation for backend applications, services, and development processes.
• Proactively monitor backend systems and investigate performance, reliability, and application issues.
• Troubleshoot and resolve production and backend system problems to maintain real-time transaction reliability.
• Collaborate with Product Managers, Designers, and other engineers to deliver high-quality platform features efficiently.
• Contribute to continuous improvements in software quality, security, scalability, and engineering practices.

Required Skills and Qualifications

Experience:

• 3+ years of professional backend software development experience using Golang, Java, or another major programming language.
• Hands-on experience developing and maintaining applications within a distributed microservices architecture.
• Practical experience with Docker and containerised application development.
• Experience with container orchestration technologies such as Kubernetes.
• Strong understanding of backend software development, testing, debugging, maintenance, and production support.
• Experience writing maintainable, reusable, and secure application code.
• Ability to troubleshoot backend applications and distributed system issues.

Soft Skills:

• Strong sense of ownership with the motivation to drive technical tasks through to completion.
• Proactive approach to identifying and resolving engineering and production issues.
• Strong collaboration skills for working effectively with engineers, Product Managers, and Designers.
• Continuous-learning mindset with an interest in modern software engineering and cloud technologies.
• Strong commitment to building secure technology that protects users and digital transactions.
• Ability to work effectively within an international and multicultural engineering environment.

Language Requirements:

• Japanese: Basic-level proficiency is sufficient for this position.
• English: Intermediate to business-level proficiency required for daily collaboration within an international engineering team; approximately TOEIC 800+ or equivalent.

Preferred Skills & Qualifications

• Experience with cloud platforms and cloud-native application development.
• Experience implementing or maintaining CI/CD automation pipelines using technologies such as GoCD, Jenkins, and Git.
• Experience working within Agile software development environments.
• Knowledge of database and data storage technologies such as Redis, PostgreSQL, MySQL, or Cassandra.
• Experience with asynchronous messaging and event-driven technologies such as Kafka or EventHub.
• Familiarity with monitoring and observability platforms such as Prometheus, Grafana, Datadog, or Splunk.
• Experience developing highly scalable, high-availability, or transaction-intensive backend systems.
• Knowledge of fraud detection, fraud prevention, payments, fintech, or other security-sensitive platforms.

About the Company

Our client is one of Japan's leading internet services and technology groups, operating a large digital ecosystem that processes significant transaction volumes every day.

Engineers work within a globally diverse technology organisation where innovation, technical ownership, and creative problem-solving are actively encouraged.

Joining this team provides hands-on exposure to high-scale backend engineering, cloud-native architecture, distributed microservices, and real-time fraud prevention technology. Your work will contribute directly to protecting millions of users and securing critical digital transactions.

Why You'll Love Working Here

• Build high-scale backend microservices supporting real-time fraud prevention and user protection.
• Strengthen your engineering expertise across Golang, Java, Docker, Kubernetes, and distributed systems.
• Solve complex technical challenges involving large transaction volumes, reliability, scalability, and security.
• Gain exposure to modern technologies including cloud platforms, CI/CD, Kafka, databases, and observability tools.
• Work alongside engineers and technology professionals in a diverse international environment.
• Make a direct impact by developing systems that help protect millions of users from fraudulent activity.
• Enjoy greater flexibility and work-life balance through a hybrid working model.
• Save on everyday expenses with access to an on-site employee food hall with meals provided.
• Receive additional support through a transportation allowance.

Don't Miss Out - Apply Now!