Backend Java Engineer

• Get to touch on new technology and grow your technical skill
• Get to work at one of the biggest e-commerce company in the world
• Work with many people with different background all over the world
• *About The Company**

This company is one of Japan’s leading online travel platforms, driven by the mission of

• *“Making People Happy with Travel.”**

This company has continuously led the travel industry through innovation and bold challenges. While firmly rooted in Japan, this company is expanding its vision globally, aiming to become a

• *Global Innovation Company**

and the world’s most trusted travel reservation service.

This company constantly pushes boundaries, embraces change, and works every day to redefine how people experience travel around the world.

• *What This Company Is Looking For**

This company is seeking passionate individuals who share its vision and enthusiasm for shaping the future of travel.

By joining this company, you will help create new travel experiences for users worldwide and take part in building services that inspire people across borders. In this company’s diverse and collaborative environment, you will be encouraged to challenge conventions, grow your skills, and contribute to meaningful innovation within the travel industry.

Role Overview In this role, you will be involved in the

• *development and operation of various travel-related services**

, including hotel reservations, airline tickets, and travel packages.

You will work on building reliable, high-quality systems using modern technologies to support increasingly diverse traveler needs. This is a highly challenging role that offers the opportunity to make a real impact in a fast-evolving industry.

This company operates

• *large-scale systems**

that handle high volumes of traffic and transactions. During peak periods, the platform processes over

• *150 reservations per second**

and supports

• *800+ search requests per second**

. As usage continues to grow, ensuring scalability, stability, and performance will be a key responsibility.

This position provides extensive exposure to complex technical challenges and offers strong opportunities for long-term career growth.

Position Details In this position, you will primarily be responsible for

• *API service development and operations**

, focusing on backend systems built with

• *Java and Spring**

.

• *Key Responsibilities Include**
• Backend development using Java and Spring-based frameworks
• System architecture design and technical decision-making
• Collaboration with related teams
• Supporting large-scale, high-traffic systems
• Handling operational issues and responding to user inquiries

As a senior backend engineer, you are expected to take ownership, mentor junior engineers, and contribute to the technical growth of the organization while serving as a role model for future engineers.

Technical Environment

Development

• Java, Spring Framework, Spring Boot, Spring Data, Spring Cloud Config
• JUnit, Apache Maven, IntelliJ IDEA

Middleware

• Oracle Database, Oracle GoldenGate for Big Data
• MongoDB, Redis, Elasticsearch
• Kafka, RabbitMQ, Kong, Nginx, Tomcat

Infrastructure

• Private Cloud

Monitoring

• Jennifer (APM), New Relic (APM)
• ELK Stack (Elasticsearch, Logstash, Kibana)
• Prometheus, Grafana
• Oracle Enterprise Manager, MongoDB Ops Manager
• PagerDuty

CI/CD

• Jenkins, SonarQube, Ansible

Tools

• Microsoft Teams, Confluence, JIRA, Bitbucket
• *Mandatory Qualifications**

Technical Experience

• Over 6 years of experience designing, developing, and operating large-scale Web APIs using Java and Spring Framework on Linux servers
• Experience with Oracle Database and NoSQL databases such as MongoDB and Redis, including table design and performance-oriented query optimization
• Hands-on experience with Elasticsearch
• Experience with Git-based development workflows (GitHub, Bitbucket, Pull Requests)

Soft Skills

• Proactively involves others to solve problems and improve situations
• Strong curiosity and continuous learning mindset
• Ability to communicate effectively with various stakeholders
• Willingness to challenge the status quo and drive improvements
• Strong team player who promotes collaboration within and across teams
• *Preferred Qualifications**
• Experience developing and operating messaging systems such as Kafka or other MQ services
• Experience operating high-traffic services, including performance tuning and access control

Language Requirement

• English: Fluent (Overall Level 4)