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Build Large-Scale Ad Platforms | Java Full‑Stack Engineer
| Location | Tokyo - 23 Wards |
| Job Type | Temporary |
| Salary | 6 million yen ~ 8 million yen |
Job Description
Join a high-impact ad tech team as a full‑stack Java engineer, taking ownership from design through production for large-scale marketing platforms. Collaborate across Tokyo and global teams to deliver reliable, data-driven systems and continuously enhance performance using modern tooling and AI.
Client Details
Our client is a leading Japanese internet and e‑commerce group with a significant advertising business supporting large-scale ad sales. The organization operates globally across Asia with distributed engineering teams and focuses on building advanced ad platforms leveraging big data and modern cloud technologies.
Description
Project Execution
- Gather and analyze requirements; translate business needs into technical solutions
- Design systems and implement features using Java (Spring Boot/Batch)
- Conduct code reviews and maintain high code quality standards
- Perform unit testing, validation, and verification
- Manage deployments (DEV/STG/PROD) and handle rollbacks when needed
- Monitor post-release performance and conduct ongoing maintenance
- Work closely with project managers, tech leads, architects, and engineers
- Partner with QA and DevOps teams for quality and reliability
- Collaborate within cross-cultural, cross-border development teams
- Proactively identify technical improvements across systems and products
- Anticipate future business needs and recommend scalable solutions
- Explore and adopt emerging technologies, including AI tools and models
Job Offer
- Opportunity to build and scale high-impact ad platforms within a major tech ecosystem
- Exposure to global, cross-functional teams across Asia
- End-to-end ownership with strong engineering autonomy
- Access to large-scale data environments and modern AI tooling
- Long-term engagement with stable project continuity
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 | Fluent |
| Minimum Japanese Level | Daily Conversation |
| Minimum Education Level | Bachelor's Degree |
| Visa Status | Permission to work in Japan required |
Required Skills
- 5+ years of hands-on software development experience
- Strong system design, coding, and problem-solving abilities
- Practical experience with Agile/Scrum methodologies
- Proactive, ownership-driven, and able to perform under pressure
- Effective communicator with both technical and non-technical stakeholders
- Experience with AI-assisted development tools (e.g., Copilot, Claude, Cursor)
- Java (Spring Boot, Batch)
- MySQL and NoSQL (e.g., MongoDB)
- Cloud/data tools (e.g., GCS, BigQuery, Dataproc or equivalent)
- Kafka (or similar streaming platforms)
- Git and issue/project tracking tools (e.g., Jira)
- Big data technologies (Hadoop, Hive, Spark)
- Frontend frameworks (React, Angular)
- Additional NoSQL (Redis, Cassandra, Couchbase)
- CI/CD (Jenkins), testing (JUnit), code quality tools (Sonar)
- BI tools (Tableau, MicroStrategy)
- Enterprise/data pipeline architecture design experience
- English: Business conversational level
- Japanese: Not required
Job Location
- Tokyo - 23 Wards
Work Conditions
| Job Type | Temporary |
| Salary | 6 million yen ~ 8 million yen |
| Industry | Software |
