Senior Frontend Engineer

We are working with a digital challenger in the energy market, making energy different for a young, urban, and digital generation. They provide private households and small to medium-sized businesses with energy from sustainable sources, offering customized electricity and gas tariffs, optionally combined with lifestyle products, all fully digital with a top-rated energy app.

The Role

Develop and continuously improve customer-facing experiences across web and mobile platforms

Focus on usability, performance, and scalability to create an engaging 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

Integrate frontend applications with API-driven backends (GraphQL / REST)

Collaborate closely with UX/UI Design, Backend, QA, and Platform Teams in Agile/Scrum setups

What You'll Need

Several years of experience developing production-ready frontend applications with React / Next.js and TypeScript

Strong fundamentals in frontend development: component architecture, performance optimization, accessibility, and modern CSS

AI-Native Developer Mindset with experience in agent-driven workflows using 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 and a distinct ownership mindset

What's On Offer

A highly motivated team with flat hierarchies and short communication paths

Workplace in the heart of Cologne with hybrid work options

Performance-based pay and 30 days of annual leave

Subsidized job ticket and free parking

Apply via Haystack today!