Backend Engineer – Java, バックエンドエンジニア – Java

PayPay Corporation

Backend Engineer developing Java/Kotlin backend applications for core banking systems at PayPay. Join a new team responsible for creating innovative banking solutions.

Posted 6/18/2026full-time🇯🇵 JapanMid-LevelSeniorWebsite

Tech Stack

Tools & technologies

JavaKotlinMicroservicesNoSQL

About the role

Key responsibilities & impact

Develop and operate backend applications in Java language (Java/Kotlin) for core banking systems
Designing and developing for both performance and stability to maintain high reliability as a financial platform
Understanding and implementing how to utilize infrastructure to solve system challenges
Designing architecture based on application requirements and selecting middleware, etc.
Performance tuning, monitoring settings, and alert response for microservices

Requirements

What you’ll need

3-5 years of backend development experience
Practical experience in Java. Excellent skills in other common programming languages
Understanding of data structures, algorithms, and the basics of object-oriented programming
Schema design in DB (RDB, NoSQL, etc.) and efficient query creation
Experience in web application development and tuning, and development with security considerations
English (Business level conversational proficiency)
Hands-on experience with AI/LLM tools (e.g., ChatGPT, GitHub Copilot, Gemini, CodeWhisperer, or similar) in professional software development.

Benefits

Comp & perks

Social Insurance (health insurance, employee pension, employment insurance and compensation insurance)
401K
Translation/Interpretation support
VISA sponsor + Relocation support

ATS Keywords

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Hard Skills & Tools

JavaKotlinbackend developmentdata structuresalgorithmsobject-oriented programmingschema designRDBNoSQLweb application development

Soft Skills

communicationproblem-solvingcollaborationadaptabilityattention to detail