Java Backend Developer

Role: Java Backend Developer – Mid/Senior

Location: Berlin (Hybrid – 2 days onsite/week)

Start date: February 2026

End date: Minimum until 2027 (long-term)

Contract type: Freelance

Context & Mission

Our client is looking for skilled Java Backend Developers to join their long-term project in Berlin. You’ll work on building and maintaining backend services as part of an international team, with most communication in English. The role is hands-on and involves close collaboration with colleagues across different areas, as well as contributing to technical design and architecture decisions.

Key Responsibilities

• Develop and maintain Java backend services following best practices.
• Build and maintain RESTful APIs and microservices.
• Collaborate with architects, QA, DevOps, and other developers to deliver high-quality solutions.
• Ensure code quality through testing and documentation.
• Participate in technical discussions and provide guidance to junior team members.
• Contribute to continuous improvement of processes and Agile practices.

Required Skills & Experience

• Professional experience in Java backend development (mid to senior level).
• Strong knowledge of Java 11+ and frameworks such as Spring Boot.
• Experience with REST APIs, microservices, and relational/NoSQL databases.
• Familiarity with testing frameworks (JUnit, Mockito) and CI/CD pipelines.
• Fluent English; German is a plus.
• Ability to work in a hybrid environment with 2 days onsite per week in Berlin.

Nice-to-Have

• Cloud experience (AWS, GCP, or Azure).
• Containerization and orchestration knowledge (Docker/Kubernetes).
• Experience with application security standards (OAuth2, JWT).