Full Stack Engineer

Job Title: Fullstack Engineer

Languages: JLPT N3 or above ( Monolingual English also Fine)

Location: Tokyo, Japan

Work Mode: Onsite

Employment Type: Contract

Experience: 4+ years

We are looking for an experienced Application Engineer with a strong background in Java development and application support. The role will involve approximately 40% development activities and 60% application support activities, including production issue resolution, application monitoring, troubleshooting, and performance improvements.

The ideal candidate should have hands-on experience in Java application development, debugging, production support, and working with cross-functional teams to ensure application stability, reliability, and continuous enhancement.

Key Responsibilities

* Development Activities (40%)

* Develop, enhance, and maintain Java-based enterprise applications.

* Analyze business requirements and implement application enhancements.

* Perform coding, debugging, and unit testing activities.

* Fix application defects and provide development-level solutions.

* Participate in code reviews and follow coding best practices.

* Optimize application performance through code improvements.

* Support application upgrades, enhancements, and new feature implementations.

* Application Support Activities (60%)

* Provide L2/L3 application support for Java-based applications.

* Monitor application health, availability, and performance.

* Analyze and resolve production incidents and application issues.

* Perform troubleshooting through log analysis and debugging.

* Conduct Root Cause Analysis (RCA) for critical production issues.

* Coordinate with development, infrastructure, database, and middleware teams for issue resolution.

* Support application deployments, releases, patches, and maintenance activities.

* Handle incident, problem, and change management processes.

* Ensure SLA compliance and timely resolution of issues.

* Prepare technical documentation, RCA reports, and support knowledge articles.

Required Skills

* Strong experience in Java, J2EE, Spring Boot, and REST APIs.

* Hands-on experience in Java application development and production support.

* Good understanding of application architecture and debugging techniques.

* Strong troubleshooting and analytical skills.

* Good knowledge of SQL and database troubleshooting.

* Experience with Linux/Unix commands and shell scripting.

* Experience with application servers such as Tomcat, WebLogic, or JBoss.

* Familiarity with monitoring and logging tools such as Splunk, Dynatrace, AppDynamics, or Grafana.

* Knowledge of CI/CD tools such as Jenkins, Git, and Maven.

* Experience with ticketing tools such as ServiceNow or JIRA.

* Understanding of Agile development and application support processes.