Full Stack Engineer — Fleet Management (m/f/d)

As a Full Stack Engineer in our Fleet Management technology team in Pullach near Munich, you will build and evolve business-critical products managing the entire vehicle lifecycle. You will own features end to end, from intuitive React interfaces to Java services in the cloud, working closely with Product, Data Science, and business experts to turn complex requirements into reliable software that creates measurable value. YOUR ROLE AT SIXT • You own features end to end, challenging unclear requirements, defining acceptance criteria, then implementing, deploying, monitoring, and validating in production instead of waiting for a detailed spec • You build and evolve systems across multiple Fleet Management domains (including Vehicle Creation and Data and third-party integrations), developing intuitive React and TypeScript experiences backed by reliable Java and Spring Boot services in a cloud-native, distributed, event-driven architecture • You collaborate with Product, Data Science, business experts, and engineering teams to turn complex processes into clear technical solutions • You use AI engineering tools across the full software lifecycle, from requirements and implementation to testing, review, and incident analysis, and you stay accountable for the correctness of what you ship • You help improve how the team builds software with AI: you evaluate and pilot new workflows, define shared standards (prompting conventions, context files, review gates), and track their effect on cycle time, defect rate, and review effort • You make quality structural through automated testing, observability, code reviews, maintainable documentation and help shape technical direction across the team YOUR SKILLS MATTER • Full-Stack Engineering You have professional experience with Java, React, and TypeScript, are comfortable across frontend and backend, and can translate complex workflows and data into clear, accessible user experiences • Backend & Architecture You have hands-on experience with Spring Boot or a comparable Java framework, understand API design, distributed systems, and asynchronous communication, and have built or operated cloud-native applications on AWS with microservices and event-driven architectures • Product Mindset You start with the problem, ask how success will be measured, and take responsibility for the outcome, not only the code • Engineering Quality You value automated testing, observability, maintainability, and systematic root-cause analysis as core parts of your craft • Modern AI Engineering You have hands-on experience with AI-assisted development in your daily work and have introduced or improved an AI-supported workflow (for example agent or skill setups, shared context files, automated test or review assistance, guardrails) with results you can explain. You validate AI output critically and know where it should not be trusted • Collaboration You communicate clearly with engineers, Product, Data Science, and business stakeholders and give and receive constructive feedback WHAT WE OFFER • Extra benefits Enjoy discounts on SIXT rent, share, ride and SIXT+, attractive vehicle leasing offers, and exclusive deals with partners for travel, tech, fashion and more • Mobility boost We support you with a monthly mobility allowance of €20 per month for even more freedom • Future security We contribute to your retirement plan and support you with capital-forming benefits to ensure you are well covered • Feel-good atmosphere Stay active with our modern SIXT gym, various leisure activities like the gaming area or the SIXT choir, and enjoy our high-quality employee restaurant • Flexibility Enjoy 30 days of vacation and a hybrid working model with flexible hours • Giving back Take one day each year to volunteer at