Senior Java Software Developer

Quick Facts

• Role: Senior Java Software Developer (Backend)

• Focus: Mobile application backend (Java/Spring), event-driven architecture, Kubernetes operations

Description

You will develop and continuously improve the backend of a mobile application using Java and Spring Boot. The role includes designing and evolving a clean Onion Architecture, integrating Firebase services, and implementing event-driven processes with Apache Kafka. You will also operate and optimize services on Kubernetes with GitOps and ArgoCD, ensuring high code quality through reviews, automated tests, and documentation.

Responsibilities

• Develop and extend a mobile backend based on Java and Spring Boot

• Design and continuously improve Onion Architecture

• Integrate Firebase services (e.g., authentication, push notifications, Firestore) into backend services

• Design and implement event-driven processes with Apache Kafka

• Operate, monitor, and optimize services on a Kubernetes cluster (deployments with GitOps and ArgoCD)

• Ensure code quality via code reviews, automated tests, and meaningful documentation

• Support team development through knowledge sharing and coaching junior developers

Requirements

• 8+ years of backend experience, ideally with Java

• Very good knowledge of Spring Boot (Spring Web, Spring Data, Spring Security)

• Experience building backend services for mobile applications, ideally offline-capable apps with synchronization and conflict handling

• Strong knowledge of modern software architectures (Onion Architecture, Clean Architecture, or MVC) and practical DDD experience

• Practical experience with Kubernetes (Deployments, Helm, ArgoCD, Ingress, scaling, troubleshooting)

• Knowledge of integrating Firebase and connecting mobile clients

• Experience implementing event-driven architectures with Apache Kafka

• Confident with Git, CI/CD pipelines, and automated tests (JUnit, Mockito, integration tests)

• German C1 and good English (spoken and written)

• Independent, structured, solution-oriented working style

Benefits

• Permanent contract

• 30 vacation days and 38-hour work week (stepwise reduction possible to 35 hours from age 50)

• Home office setup with equipment and company mobile phone

• Capital-forming benefits and company pension plan

• Choice between macOS and Windows

• Subsidized sports via EGYM Wellpass, in-house yoga

• Bike leasing and loan bikes

• Programs to support junior leadership and professional career paths