Senior Software Engineer, Fullstack - All Genders

Role overview Own product work across the frontend and backend, using rapid experimentation to improve user and business outcomes. You’ll turn ideas into testable hypotheses, ship changes, assess results, and extend features wherever the problem requires—from user interfaces to APIs and services.

Responsibilities - Design and deliver product experiments, then use their results to guide follow-up work. - Build and maintain interfaces using React, Next.js, TypeScript, and parts of a legacy JavaScript and Redux application. - Extend backend services and GraphQL APIs to support product features and experiments. - Instrument features with reliable tracking that respects user consent. - Improve performance across devices and collaborate with product, design, analytics, and engineering colleagues on scheduling challenges.

Requirements - Hands-on experience with product growth work, such as A/B testing, funnel optimization, activation, or conversion. - Professional experience with JavaScript, TypeScript, React, and Next.js, plus comfort working in older JavaScript and Redux code. - Experience building production applications with GraphQL and Apollo Client. - Ability to work across the stack, investigate unfamiliar code, and use AI coding tools as part of day-to-day development. - A computer science or related degree, or equivalent practical experience. - Based in Germany and authorized to work there; visa sponsorship and relocation support are unavailable.

Nice to have - Backend service development, particularly with Java, and experience designing GraphQL APIs. - Familiarity with microservices, Kafka or other event-driven systems, or Go. - Experience with experimentation, feature flag, analytics tracking, or billing tools.