Full Stack Developer at Certisign, designing user interfaces and developing backend solutions. Collaborating on scalable software architecture across teams to ensure client requirements.
About the role
- Software Engineer responsible for developing AI-integrated features from backend to frontend for an energy transition startup in Germany. Collaborating on security practices and data integration.
Responsibilities
- End-to-end feature development: Build and own product features from concept to production, moving confidently between our backend (Kotlin/Spring Boot) and frontend (React).
- AI implementation: Drive our AI roadmap by integrating LLM APIs (OpenAI, Gemini, Anthropic) and turning them into tangible product value.
- Agentic systems & workflows: Design and implement advanced agentic patterns, including tool/function calling, ReAct loops, multi-step orchestration, and intelligent memory systems.
- Collaborative engineering: Work closely with our Data Engineer on data-to-product integration and contribute to our CI/CD pipelines to ensure reliable, high-quality deployments.
- Security & reliability: Apply security best practices with a focus on prompt-injection defenses, output validation, and data privacy.
Requirements
- JVM & Python proficiency: Experienced in — or highly motivated to make your primary language — Kotlin/JVM (Spring Boot, Hibernate) and solid in Python (FastAPI).
- AI expertise: Hands-on experience integrating LLM APIs into production products. Familiarity with RAG, context management, and reasoning patterns. Experience with LangGraph is a strong plus.
- Tech stack foundations: Comfortable with PostgreSQL and have basic knowledge of TypeScript (React/Redux). Familiarity with GCP is an advantage.
- Security mindset: Build with a security-first approach (OWASP Top 10) and understand the specific challenges of LLM-based applications.
- Language: Strong English is required; proficient German skills are a plus.
Benefits
- Benefits program, team offsites, office parties, and team working days.
- Competitive compensation.
Job title
Job type
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Not specified
Degree requirement
Tech skills
Location requirements
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