Frontend Software Engineer - React/JavaScript (m/f/d)

Join us at SIXT as a Backend Engineer and immerse yourself in an exciting journey of tech innovation in the heart of Lisbon! We are seeking a skilled Backend (Java) Developer to join out technology team who has the hunger to solve our complex technical and business challenges. We are building a next generation mobility ecosystem based on cloud-native micro services platform. If you want to be part of our journey and make an impact - apply now! YOUR ROLE AT SIXT • You turn ambiguous product problems into clear, testable specifications that agents can execute against • You run end-to-end agent workflows to build features, then review the resulting change as a whole - correctness, architectural consistency, and drift • You own what your agents ship to production, debugging to root cause and encoding prevention through tests, rules, or agent constraints • You ship small-to-medium features end-to-end with minimal guidance, including deployment • You build production-quality, reusable React components and integrate reliably with backend and third-party systems • You challenge unclear requirements, weigh business and user trade-offs, and communicate decisions and risks clearly to product and engineering partners YOUR SKILLS MATTER • Education You hold a Bachelor's or Master's degree in Computer Science or a related field, or you have experience with the tools and skills required • Experience You bring 3-6 years of frontend software engineering experience • Hard Skills You have strong React.js and framework-based JavaScript know-how, including component contracts, state management, and rendering and performance behaviour • Know-how You understand how the browser parses, renders, and paints a page, and write semantic, accessible HTML by default • Tools You are proficient with HTML, CSS, JSON, build tools, Git, and confident debugging in Chrome DevTools • Motivation You are comfortable working with AI coding tools daily, with the judgment to verify and correct their output WH