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Lead Java Developer

Kepler SearchLuxembourgLuxembourgPosted 1 Aug 2026

Quick Overview

Work Type
On Site
Schedule
Full Time
Level
Mid Senior

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.

Skills

SQL
Spring
Spring Boot
ELK
OWASP
Angular
Capacitor
GitLab CI
Java
iOS
Android

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