Senior API Developer – Java/Spring Boot & AI Integration

About the role

We are seeking a Senior API Developer to design and deliver high‑performance backend services and AI‑enabled solutions for our clients in Germany. The role is fully onsite in Bad Homburg (or Nuremberg) and requires deep expertise in modern Java, Spring Boot, and large‑language‑model integration.

Key responsibilities

• Design, develop, and maintain scalable RESTful APIs using Java 21+ and Spring Boot.
• Build enterprise‑grade backend services with J2EE technologies.
• Integrate LLM‑powered chatbots and other AI‑driven components into existing platforms.
• Define and implement API integrations, backend workflows, and micro‑service architectures.
• Ensure services meet performance, reliability, security, and maintainability standards.
• Participate in code reviews and follow engineering best practices.
• Collaborate with cross‑functional technical teams to deliver business‑critical solutions.

Required profile

• Senior‑level professional with several years of experience in Java backend development.
• Strong hands‑on background with Spring Boot, REST API design, and J2EE.
• Proven experience integrating AI/LLM solutions or chatbots.
• Familiarity with API security concepts such as OAuth2 and JWT.

Required skills

• Java 21+
• Spring Boot
• REST APIs
• J2EE
• JavaScript
• Git / GitLab
• Maven
• LLM, AI chatbot, GenAI
• Microservices architecture
• OAuth2 / JWT
• Cloud platforms and CI/CD pipelines