Your role 💼
We are looking for an Application Migration & Modernisation Engineer to support a large-scale transformation initiative focused on migrating legacy ESB-based services into modern, cloud-native architectures.
This role is particularly suited for profiles with strong experience in integration and middleware modernisation, moving legacy systems toward Spring Boot microservices deployed on OpenShift.
Key Responsibilities includes:
1. Application Migration & Modernisation
Migrate services from Java 6–11, SwitchYard, Red Hat Fuse / EAP 6 to Java 25 and Spring Boot 4
Rewrite Camel/Fuse routes and SwitchYard services into standalone Spring Boot components
Containerise services and deploy them on OpenShift
Maintain and evolve REST and SOAP APIs
Ensure backward compatibility with existing systems
2. Messaging & Integration
Contribute to migration from ActiveMQ to Kafka
Ensure reliability during coexistence phases
Implement integration patterns:
Idempotence
Error handling
Dead-letter queues
Message ordering
At-least-once delivery
Document data flows and messaging contracts (Avro/JSON, topics, consumer groups)
3. DevOps, CI/CD & Deployment
Maintain and enhance GitLab CI/CD pipelines
Manage build, testing, containerisation and deployment processes
Apply GitOps practices with ArgoCD
Work with Docker, Helm, Kustomize and OpenShift
Contribute to Infrastructure as Code for environment reproducibility
4. Quality, Reliability & Observability
Ensure stability and performance of migrated services
Implement automated testing (unit, integration, non-regression)
Use tools such as JUnit 5, Testcontainers, WireMock
Implement monitoring and logging:
Prometheus
Micrometer
Grafana
ELK
OpenTelemetry
Provide Level 3 support
Produce documentation and runbooks
Soft Skills
Strong analytical and problem-solving skills
Ability to work in complex technical environments
Good communication and collaboration skills
Autonomous and solution-oriented mindset
Attention to quality and detail
Requirements 💡
- Degree in Computer Science, Software Engineering or related field
- Minimum 5 years of experience in Java development and system integration
- Strong experience with Java (11–25) and Spring Boot (2.x–4.x)
- Experience with REST and SOAP APIs
- Knowledge of Apache Camel, Red Hat Fuse, SwitchYard
- Experience with ActiveMQ/JMS and Kafka
- Strong DevOps knowledge:
- GitLab CI/CD
- Docker
- Kubernetes / OpenShift
- ArgoCD
- Helm / Kustomize
- Knowledge of: Clean Code; Automated testing; SonarQube; OWASP
- Nice to have: Kubernetes certifications (CKA / CKAD); Red Hat OpenShift certification (EX280)
📍 Where: Luxembourg, Full on-site presence in Luxembourg (5 days per week)
🌱 What We Offer
✨ A dynamic, young, and fast-growing environment
🔄 Flexible thinking and working approaches
🎓 Hands-on experience in a stimulating, project-based context
👩 🏫 Opportunities to learn from industry professionals
📚 On-the-job training (and more)
🚀 The chance to work on real projects with tangible impact
The chance to work on real projects with tangible impact
🌍 Inclusion & Equal Opportunity
We believe in people, diversity, and meritocracy. Our recruitment processes are open to everyone—regardless of gender, ethnicity, orientation, or ability. For us, talent is a matter of energy, not labels.
🔗 Discover more about us #BTO
Explore our world at 🌐 www.relatech.com