Senior Java Engineer (German language)

About the Role

In this role, you will lead the modernization of an established platform, moving it from a monolithic architecture toward cloud-native microservices. You will influence key decisions across Java services, containerization, observability, and automated delivery, helping business-critical systems scale reliably. Working with a distributed engineering team, you will collaborate directly with German-speaking stakeholders.

Responsibilities

• Redesign a monolithic platform into loosely coupled microservices using Java and Spring Boot, with React and TypeScript where required
• Drive containerization of legacy JVM applications with Docker or Podman, including JVM tuning and externalized configuration and state
• Collaborate with architects, DevOps engineers, QA specialists, and client stakeholders to plan technical changes and release them safely
• Build and maintain CI/CD workflows using ArgoCD and GitOps practices to automate build, testing, and deployment
• Implement OpenTelemetry-based observability across logs, metrics, and traces using Grafana, Prometheus, Loki, and Mimir
• Develop data flows with PostgreSQL, Redis, and Kafka while managing database changes through Liquibase or Flyway
• Deploy Kubernetes services with Helm, including Ingress, TLS, NetworkPolicies, and secure secrets management
• Strengthen application and container security with HashiCorp Vault or External Secrets Operator, SonarQube, and Trivy

Requirements

• Proven experience modernizing monolithic applications into microservices-based, cloud-native solutions
• Advanced Java and Spring Boot expertise, ideally across Java 11, 17, or 21, plus working knowledge of React and TypeScript
• Practical experience with the testing pyramid (unit, integration, system, end-to-end) and Java testing frameworks
• Hands-on expertise with Docker, Kubernetes, and Helm, including Kubernetes networking and secrets management
• Practical knowledge of CI/CD, ArgoCD, GitOps, Linux, and Bash, with experience in Azure DevOps or Harness
• Solid experience with PostgreSQL, Redis, Kafka, and schema registries such as Apicurio or Avro
• Applied knowledge of OpenTelemetry-based observability and restricted build environments using artifact proxies or curated registries
• Experience with transmission system operators or similar energy infrastructure companies
• Cloud Native certifications such as CKA or CKAD
• Hands-on experience with Harness, ArgoCD, or Keycloak/OIDC
• Comfortable working with agile delivery practices and collaboration tools such as Scrum, SAFe, Jira, and Confluence
• Fluent English (C1+) and German (B2+) for client communication, technical meetings, and documentation