Senior Frontend Engineer

About the job We're working with a leading digital energy provider that disrupted the energy market by making sustainable energy accessible and tailor-made for a young, urban, and digital generation. They combine energy tariffs with lifestyle products and offer a fully digital experience through an award-winning app. Are you ready to join a team that values innovation and makes a real impact on the future of energy? The Role Develop and continuously improve customer-facing experiences across modern digital platforms (web and mobile). Focus on usability, performance, and scalability to create an inspiring end-to-end energy experience. Build and maintain key customer journeys including login, account management, billing, payments, and self-service features. Develop with Next.js / React and TypeScript using a component-oriented approach. Collaborate closely with UX/UI design, backend, QA, and platform teams in Agile/Scrum environments. Contribute to frontend standards, testing strategies, and CI/CD quality processes. What You'll Need Several years of experience developing production-ready frontend applications with React / Next.js and TypeScript. Strong foundation in frontend development: component architecture, performance optimization, accessibility, and modern CSS. AI-Native Developer Mindset: Proficient in agent-driven workflows with tools like Claude Code, Cursor (Composer), or Windsurf (Cascade). Experience with API-first platforms and authentication flows. Pragmatic approach to testing and confident working in CI/CD-driven teams. Strong communication skills in German and English, with a pronounced ownership mindset. What's On Offer A highly motivated team with flat hierarchies and short communication channels. A workplace in the heart of Cologne with the option for hybrid work. Performance-based compensation and 30 days of annual leave. Subsidy for job tickets and free parking. Apply via Haystack today!