AI Test Engineer (m/f/d)

AI Test Engineer (m/f/d)

Company: SIXT
Location: Lisbon, Portugal (Hybrid)
Department: TECH & Engineering
Employment Type: Full-time

About SIXT:

SIXT is a global mobility leader with EUR 4.00 billion revenue and ~9,000 employees.

About the Role:

SIXT seeks a QA engineer to test virtual agents and AI-powered customer service workflows. The role combines classical QA expertise with agentic automation and conversational AI knowledge.

Key Responsibilities:

• Design end-to-end test plans for customer service virtual agents across voice, chat, and email channels
• Build and maintain test suites validating autonomous workflows (booking changes, billing, damages)
• Define and monitor quality metrics: resolution rate, deflection, CSAT, safety violations
• Develop test data and synthetic scenarios for edge cases, ambiguous queries, multilingual requests
• Evaluate agent behavior through reasoning traces and tool-use decisions
• Implement automated testing frameworks for conversational flows, APIs, integrations
• Contribute to LLMOps/CI/CD pipelines for regression detection
• Conduct bias, fairness, and safety testing aligned with company policies
• Collaborate cross-functionally on requirements and acceptance criteria

Required Qualifications:

• 2-3 years software QA/test engineering experience
• Strong understanding of testing principles: functional, regression, integration, performance
• Hands-on experience testing AI/ML systems (LLM chatbots, recommendation engines)
• Familiarity with multi-agentic systems, frameworks like LangChain, AWS AgentCore
• Python scripting and REST API testing skills
• Understanding of LLMOps/MLOps: versioning, monitoring, rollback strategies
• Customer service process and KPI experience or interest
• Fluent English; German or additional languages preferred

Benefits:

• 28 vacation days plus birthday day off, 1 volunteer day annually
• Hybrid work model with flexible hours, no dress code
• SIXT service discounts and partner benefits
• Training programs, conferences, internal tech talks
• Private health insurance
• Coverflex advantage system