Software Engineer (APS)

Rakuten, Inc. (TYO: 4755) is a global leader in internet services, spanning e-commerce, fintech, digital content, and communications. Our mission is to empower people and society through innovation and entrepreneurship. With over 10,000 employees worldwide, we operate at the intersection of massive scale and cutting-edge technology.

The Ad Product Section (APS) division is a high-performance, global team distributed across Tokyo, Singapore, India, and China. We pride ourselves on being a hub of technical excellence, where motivated, diverse, and talented engineers collaborate to solve complex problems at scale.

We are looking for a motivated Software Engineer with 2–3 years of experience to join our engineering team. You will contribute to the full software development lifecycle, building and maintaining robust, scalable features within our Ad Tech ecosystem. This role is perfect for an engineer who is eager to sharpen their skills in Java and Cloud-native development while working at the forefront of AI-augmented software engineering.

If you are a builder who values technical rigor, thrives in cross-functional environments, and is eager to contribute to Rakuten’s expansive global ecosystem, we want to talk to you.

Responsibilities

Project Execution & Engineering Excellence

• Feature Implementation: Translate technical specifications into clean, maintainable, and efficient code. You will own the implementation of specific modules from development through to deployment.
• Quality Assurance: Participate in peer code reviews, ensuring adherence to design patterns, security best practices, and team coding standards.
• AI-Augmented Development: Utilize AI-powered coding assistants (e.g., GitHub Copilot, Cursor) to accelerate your development workflow. You will be responsible for ensuring that all AI-generated code is verified for security and accuracy before it reaches production.

Productive Contribution

• System Maintenance: Assist in identifying and resolving technical debt. You will help maintain the health of our product ecosystem by proactively addressing bugs and performance bottlenecks.
• Workflow Automation: Use prompt engineering and internal tools to automate repetitive tasks, such as writing unit tests, drafting documentation, and refactoring legacy code.

Collaboration & Growth

• Team Integration: Work closely with senior engineers, product managers, and architects to understand business requirements and translate them into functional technical solutions.
• Continuous Learning: Stay current with emerging technologies and AI tools. We encourage a culture of knowledge sharing, where you will contribute to team discussions and documentation.

Qualifications

Core Requirements (The "Must-Haves")

• Experience: 2+ years of professional software engineering experience, with a solid understanding of the full SDLC in a production environment.

• Technical Foundation: Hands-on experience with Java (Spring Boot/Batch) and exposure to Cloud-native architectures (GCP ecosystem preferred: BigQuery, DataProc, Composer).

• Data Proficiency: Working knowledge of both relational (MariaDB/MySQL) and NoSQL (MongoDB) databases.

• AI-Fluency: Demonstrated experience using AI-assisted coding tools (e.g., Cursor, GitHub Copilot) to improve your individual coding velocity and code quality.

• Problem Solving: A strong analytical mindset with the ability to break down complex business requirements into actionable coding tasks.

• Communication: Ability to clearly explain technical challenges and progress to both technical and non-technical team members.

• Soft Skills & Ownership: A "get-things-done" mindset with demonstrated accountability for the output. Excellent communication skills, with the ability to work with cross-functional and cross-regional teams.

Technical Proficiencies

• Languages & Frameworks: Java (Spring Boot/Batch), JavaScript/TypeScript (HTML5/CSS3).

• Data & Infrastructure: MariaDB/MySQL, MongoDB, GCP (BigQuery, DataProc, Composer).

• Tools & Process: Version Control (Git), Agile/Scrum, Task Management (Jira).

Preferred Qualifications (The "Nice-to-Haves")

• Modern Frontend: Experience with React.js or Angular.

• Big Data/Messaging: Familiarity with Spark, Kafka, Redis, or RabbitMQ.

• DevOps/Testing: Hands-on experience with CI/CD pipelines (Jenkins), JUnit, and SonarQube.

• Domain Knowledge: Previous experience in AdTech or high-traffic systems is a plus.

• AI Orchestration: Exposure to frameworks like LangChain or n8n is highly valued.

• Observability/Data Visualization: Familiarity with ELK, Grafana, BI tools (MicroStrategy, Tableau) for data-driven decision-making.
  

  Rakuten is an equal opportunities employer and welcomes applications regardless of sex, marital status, ethnic origin, sexual orientation, religious belief or age.