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Lead Java Developer

Kepler SearchLuxembourg🇱🇺LuxembourgPosted 1 Aug 2026

Quick Overview

Seniority
Mid Senior
Employment type
Full Time
Work mode
On Site
Location
Luxembourg, Luxembourg
SQLSpringSpring BootELKOWASPAngularCapacitorGitLab CIJavaiOSAndroid

Job Description

Lead Java Developer

Luxembourg

On-site

Contract

One of our clients in Luxembourg is searching for a Senior Java Developer to join them on an exciting project focused on the evolution and modernisation of a business-critical software platform.

The Senior Java Developer will work closely with cross-functional teams to enhance the reliability, security, and performance of existing applications while contributing to the delivery of new features and modernisation initiatives across web and mobile environments.

Required Tasks;

  • Contributing to application reliability through version upgrades, troubleshooting, and obsolescence management.
  • Analysing logs and monitoring data to diagnose complex technical issues and perform root cause analysis.
  • Implementing security best practices, including authentication, authorisation, secret management, and vulnerability remediation.
  • Improving application performance, code quality, telemetry, and error handling.
  • Providing technical expertise during redesign and modernisation projects.
  • Supporting secure and stable production deployments through technical documentation and test automation.

Required previous skills;

  • Minimum of 5 years' experience as a Java Developer.
  • Strong knowledge of Java (17+) and the Spring ecosystem (Spring Boot and Spring Security).
  • Experience with root cause analysis and application monitoring tools.
  • Knowledge of frontend technologies such as Angular and an understanding of mobile environments (iOS, Android and Capacitor).
  • Proficiency with MS SQL databases.
  • Experience with observability tools such as OpenTelemetry and/or the ELK stack.
  • Experience working with OpenShift and GitLab CI.
  • Strong understanding of secure development practices and OWASP standards.

Please note that this position requires regular onsite presence in Luxembourg.

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