Join our Data Science team and help shape SIXT's Customer Service Transformation. Our AI assistant CARA authenticates customers, manages real reservations, and handles policy questions across 10+ markets and 7 languages. She's a production multi-agent system with write access to SIXT's booking platform, running on chat, app, WhatsApp, and soon voice. Your work will impact millions of customers and deliver measurable business results.

YOUR ROLE AT SIXT

• You own agents end to end: prompt, orchestration graph, tools, evals, deployment, dashboard. You write the agent logic and watch your own traces in production

• You translate business problems into agent capabilities, working with product, business and customer service stakeholders to define tool calls and sub-agents, and you build for real transactions with step-up authentication, guardrails, idempotent case handling, and handover into Salesforce and Genesys

• You make quality measurable, extending our evaluation harness with LLM-as-judge rubrics, tool-trajectory assertions and prompt A/B suites that gate every release

• You engineer for cost and latency as much as accuracy: multi-provider model routing with fallbacks, prompt caching, small models where small models win

• You collaborate across the stack with software engineers, data scientists, MLOps and platform teams, balancing bespoke agent logic against reusable platform capability, and you raise the floor around you by sharing agentic and LLM engineering knowledge with colleagues and helping other teams integrate Agentic AI into their products

• You work with the following stack context: Python with LangGraph and LangChain, deployed as containerised agents on AWS Bedrock AgentCore with MCP sub-agents and OpenAPI tool federation. Multi-provider fallback chains with Anthropic and OpenAI LLMs behind Bedrock Guardrails. Next: CARA for Voice

YOUR SKILLS MATTER

• Engineering foundation You're an engineer first with strong, hands-on software engineering, real production ownership, excellent Python skills, and solid AWS cloud experience

• Agentic experience You have built tool-calling agents with LangGraph/LangChain or equivalent frameworks and shipped them to actual users rather than keeping them in notebooks

• Model and prompt expertise You're hands-on with frontier and open models like Anthropic Claude, OpenAI, AWS Bedrock, and open-source models such as Llama, with a clear point of view on when to use which, and you treat prompt engineering as an engineering discipline: versioned, reviewed, evaluated, A/B tested

• LLMOps paradigm You know and have applied LLMOps: tracing, evals, guardrails, token and latency budgets, continuous integration and deployment

• Bonus skills MCP, real-time voice AI (WebRTC, SIP, streaming STT/TTS), event-streaming pipelines, TypeScript/React, or contact-centre platforms like Genesys and Salesforce add value

• Motivation and communication You're extremely motivated, passionate about learning, bring a genuine can-do attitude, communicate fluently in English, and appreciate cultural diversity

WHAT WE OFFER

• A Global Tech Hub in Lisbon Join a thriving international tech community and work alongside engineers, product experts, and business teams who turn ideas into real impact. Our hubs at Factory Lisboa in Beato and ARTs Lisboa in Parque das Nações are where great tech gets built

• Learning & Knowledge Exchange Level up through regular events with internal and external speakers. We value curiosity, continuous learning, and open exchange – across teams, disciplines, and borders

• Flexible Work Setup Two office days a week, flexible hours, and modern spaces built for both deep focus and team collaboration – work the way that brings out your best

• Time Off & Wellbeing Enjoy 28 vacation days per year, an additional day off on your birthday, one volunteer day annually, and private health insurance that also covers your spouse and children free of charge

• Practical Everyday Benefits Get a yearly Coverflex allowance and a daily meal allowance to make everyday life a little easier

• SIXT Perks Get exclusive rates on all SIXT services, with special discounts extended to your family and friends. Because great perks are even better when you can share them

About us:

We are 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. At SIXT, top-tier customer experience and outstanding customer service are our highest priorities. We believe in true entrepreneurship and long-term stability and align our corporate strategy with foresight. Get started with us and apply now!