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Job ID : 1577398
Date Updated :
February 8th, 2026
Senior Java Engineer - E‑commerce
Senior Java Engineer - E‑commerce Platform
| Location | Tokyo - 23 Wards |
| Job Type | Temporary |
| Salary | Based on hourly rate |
Job Description
This is a senior Site Reliability Engineer position focused on designing, building, and operating core shopping cart and checkout APIs for a large‑scale online marketplace. You will play a key role in ensuring performance, reliability, and scalability while guiding other engineers and driving best‑practice DevOps and SRE processes.Client Details
Our client is a major internet services and e‑commerce company operating one of Japan's largest online marketplaces and related digital platforms. The engineering organization supports high‑traffic, business‑critical systems, offering an international environment where English is used daily and engineers work with modern cloud and container technologies.Description
As a Senior Site Reliability Engineer, you will:- Design, develop, and operate APIs that power the core shopping cart and checkout systems for a high‑traffic e‑commerce platform
- Take end‑to‑end ownership across design, development, deployment, and operations as part of a dedicated SRE team
- Lead technical initiatives around middleware and cloud‑based services to improve availability, scalability, and performance
- Drive incident response and troubleshooting for large‑scale online systems, identifying root causes and implementing long‑term fixes
- Plan and execute load testing and capacity planning to ensure systems can handle peak traffic and future growth
- Establish and promote best practices across the software development lifecycle, including coding standards, code reviews, CI/CD, testing, and monitoring
- Collaborate closely with application engineers, infrastructure teams, and product stakeholders to deliver robust and maintainable solutions
- Provide technical leadership to multiple engineers, mentoring team members and helping to shape SRE standards and culture
Job Offer
- Senior‑level SRE position with clear technical leadership responsibilities
- Opportunity to work on core, business‑critical systems used by millions of users
- Exposure to modern cloud, container, and DevOps practices in a high‑scale environment
- Collaborative, international engineering culture where English is used for daily communication
- Strong platform for career growth in SRE, architecture, or technical leadership within a major technology organization
To apply online please click the 'Apply' button below. For a confidential discussion about this role please contact Serena Wu on +81 3 6627 6137.
General Requirements
| Minimum Experience Level | No experience |
| Career Level | Mid Career |
| Minimum English Level | Business Level |
| Minimum Japanese Level | None |
| Minimum Education Level | Bachelor's Degree |
| Visa Status | Permission to work in Japan required |
Required Skills
You are an experienced engineer with a strong background in both development and operations, ideally within large‑scale online services. You are comfortable leading others, making architectural decisions, and taking ownership of production reliability.
Must‑have skills and experience:
- 5+ years of hands‑on Java development experience
- Solid experience developing Web APIs using RESTful technologies
- Proven experience operating and supporting large‑scale online systems, including incident response
- Deep understanding of the full software development lifecycle: coding standards, code reviews, source control, build pipelines, testing, and production operations
- Ability to proactively design and implement high‑performance, reliable, and maintainable code
- Practical DevOps experience (e.g., CI/CD pipelines, automation, infrastructure as code, or similar practices)
- Language:
- No Japanese required
- Daily conversational level English (for meetings and collaboration)
Preferred (nice‑to‑have) skills:
- Experience creating or managing automation / operational tools such as Jenkins
- Experience implementing system monitoring and alerting
- Hands‑on production troubleshooting experience in mission‑critical environments
- Experience with container technologies such as Docker and Kubernetes
- Design and development experience using RDB, KVS, and/or NoSQL databases
If you meet most requirements and are eager to grow, we'd like to hear from you.
Job Location
- Tokyo - 23 Wards
Work Conditions
| Job Type | Temporary |
| Salary | Based on hourly rate |
| Hourly Rate | ¥3000 - ¥5000 |
| Industry | Software |
