Lisbon, /, Portugal Hybrid

SIXT is hiring an AI Test Engineer

Ensure the reliability, safety, and quality of virtual agents and generative-AI workflows across customer service channels. Design and execute test strategies for LLM- and agent-based systems by combining traditional QA practices with expertise in conversational AI and agentic automation.

Responsibilities

  • Create and carry out end-to-end test plans for virtual customer service agents across voice, chat, and email platforms.
  • Develop and maintain test suites for agentic AI systems that validate autonomous processes like booking modifications, billing tasks, and damage handling.
  • Establish and track AI quality metrics including resolution rates, customer deflection, customer satisfaction scores, and safety compliance.
  • Generate test data and synthetic scenarios to evaluate edge cases, ambiguous user inputs, and multilingual interactions.
  • Assess agent behavior by analyzing reasoning paths, tool usage decisions, and memory consumption patterns.
  • Build and enhance automated testing frameworks for conversational interactions, APIs, and system integrations.
  • Support LLMOps and CI/CD pipelines to automatically identify regressions in AI models and workflows.
  • Conduct testing for bias, fairness, and safety in alignment with company policies and regulatory standards.
  • Work with cross-functional teams to help define requirements and acceptance criteria.
  • Record and report defects, test outcomes, and actionable insights clearly for technical and non-technical stakeholders.

Requirements

  • 2 to 3 years of professional experience in software quality assurance or test engineering.
  • Solid knowledge of testing methodologies including functional, regression, integration, and performance testing.
  • Practical experience testing AI or machine learning systems such as LLM-powered chatbots or recommendation engines.
  • Familiarity with multi-agentic systems and agentic frameworks like LangChain and AWS AgentCore.
  • Proficiency in Python scripting.
  • Experience testing RESTful APIs.
  • Understanding of LLMOps and MLOps practices including model versioning, monitoring, and rollback procedures.
  • Strong analytical thinking, documentation abilities, and communication skills.
  • Fluent in English.

Nice to Have

  • Knowledge of German or other languages is preferred.

Tech Stack

Python, REST API, LangChain, AWS AgentCore, LLMOps, MLOps, CI/CD, Generative AI, Conversational AI, Agentic AI

Benefits

  • 28 days of paid vacation per year
  • One additional day off for your birthday
  • 1 paid volunteer day annually
  • Hybrid working model
  • Flexible working hours
  • No formal dress code
  • Access to discounts on car rental, car sharing, ride-hailing, and SIXT+ services
  • Partner discount programs
  • Opportunities to participate in training initiatives
  • Attendance at external industry conferences
  • Internal developer and technology presentations
  • Private health insurance coverage
  • Coverflex employee benefits platform

Work Arrangement

Hybrid working model with flexible working hours

  • Commitment to top-tier customer experience
  • Focus on exceptional customer service
  • Encouragement of entrepreneurial mindset
  • Long-term corporate stability
  • Strategic foresight in business planning

Additional Information

  • English language fluency is required.
  • Proficiency in German or additional languages is an advantage.
  • Work-life balance and flexibility includes a relaxed, no-dress-code policy.
  • Training and development opportunities include attendance at external conferences and internal tech talks.
  • Health and well-being are supported through private health insurance.
  • Employee benefits include access to the Coverflex advantage system.
Required Skills
PythonREST APILangChainAWS AgentCoreLLMOpsMLOpsCI/CDGenerative AIConversational AIAgentic AI PythonREST APILangChainAWS AgentCoreLLMOpsMLOpsCI/CDGenerative AIConversational AIAgentic AI
About company
SIXT
A globally leading mobility service provider with a revenue of €4.00 billion and around 9,000 employees worldwide. Our mobility platform ONE combines our products SIXT rent (car rental), SIXT share (car sharing), SIXT ride (taxi, ride, and chauffeur services), and SIXT+ (car subscription), giving our customers access to our fleet of 350,000 vehicles, the services of 4,000 cooperation partners, and around 5 million drivers worldwide. Together with our franchise partners, we are present in more than 110 countries at 2,000 rental stations.
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Job Details
Department Software Development
Category qa_testing
Posted 2 months ago