At SIXT, we are looking for an AI Test Engineer (m/f/d) to ensure our virtual agents and Generative-AI–powered workflows deliver reliable, safe, and excellent support across all customer service channels. You will design and run intelligent test strategies for LLM- and agent-based systems.
What You'll Do
- Design and execute end-to-end test plans for customer service virtual agents across voice, chat, and email.
- Build and maintain agentic AI test suites validating autonomous workflows for booking changes, billing, and damages.
- Define and monitor AI quality metrics like resolution rate, deflection, CSAT, and safety violations.
- Develop test data and synthetic scenarios for edge cases, ambiguous queries, and multilingual requests.
- Evaluate agent behavior through reasoning traces, tool-use decisions, and memory usage.
- Implement and improve automated testing frameworks for conversational flows, APIs, and integrations.
- Contribute to LLMOps and CI/CD pipelines to automatically detect regressions.
- Perform bias, fairness, and safety testing aligned with SIXT policies and regulations.
- Collaborate with cross-functional teams to refine requirements and acceptance criteria.
- Document defects, test results, and insights clearly for stakeholders.
What We're Looking For
- 2-3 years of experience in software QA or test engineering.
- Strong understanding of functional, regression, integration, and performance testing principles.
- Hands-on experience testing AI or ML systems such as LLM chatbots or recommendation engines.
- Familiarity with multi-agentic systems concepts and frameworks like LangChain or AWS AgentCore.
- Scripting skills in Python and experience with REST API testing.
- Understanding of LLMOps and MLOps practices: versioning, monitoring, and rollback strategies.
- Experience or interest in customer service processes and KPIs.
- Excellent analytical, documentation, and communication skills.
- Fluency in English.
Nice to Have
- German or additional languages are a plus.
Technical Stack
- Python
- REST API
- LLM & Generative AI
- AWS AgentCore
- LangChain
Benefits & Compensation
- 28 days of vacation annually.
- An additional day off for your birthday.
- 1 volunteer day per year.
- Hybrid working model and flexible working hours.
- No dress code.
- Discounts on SIXT rent, share, ride, and SIXT+ services.
- Partner discounts.
- Access to training programs, external conferences, and internal development talks.
- Private health insurance.
- Coverflex advantage system.
Work Mode
This position follows a hybrid working model, blending in-office collaboration with remote flexibility.
SIXT is an equal opportunity employer.
