Staff Frontend Engineer / Frontend Architect (m/f/d)

IntroductionTeaser Two products, two backends, one frontend vision: build the AI-first frontend platform and design system that lets our engineers, product managers and designers ship UI at speed. A senior hands-on role with architect-level influence, no people management, and our CPTO as your executive sponsor. Role at a glance Level: Staff/Principal-level individual contributor – technical leadership, no direct reportsReporting line: VP Engineering. Executive sponsor: our CPTOProducts: FactFinder NG (React on a Java backend) and Infinity (React on a .NET/F# backend)Stack you'll shape: React, TypeScript, Web Components, design tokens, Storybook, AI coding tools (Claude Code, Cursor, MCP-based tooling)Team: Product & Technology organization of around 25 people, led by our CPTO, working in a product trio model with product and designLocation: Berlin; Munich, Pforzheim or Stockholm possible – hybrid with 2–3 office days per week; occasional travel (Start: as soon as possible About FactFinder FactFinder is one of the leading product discovery platforms for European eCommerce. For more than 20 years we've applied AI and machine learning to product search, navigation, personalization and recommendations. Our Product Discovery Experience (PDX) spans two products: FactFinder NG, an exact and highly configurable search, and Infinity, a self-learning, behavioral discovery engine. More than 2,000 customers generate over €160 billion in annual GMV on our platform. We're around 90 people with a new management team, a clear growth plan and reknown investors behind us. Right now we're rebuilding our product and tech organization around an AI-first way of working and agentic commerce – and this role sits at the center of it. Why this role exists Our two products run two React frontends with very different technical roots. We need a vision, an architect, and an owner — someone who will unify them into a single, efficient system, build the shared design system on top, and enable product managers and designers to prototype and ship production-grade UI themselves with AI tooling. Incrementally, without a big-bang rewrite, and while both products keep shipping. Your missionWhat you'll do Define and drive the target frontend architecture across both React products – one consistent, efficient React-based system, migrated step by stepBuild and own our shared design system: tokens, component library and Web Components for embeddable shop UI, tightly aligned with Product DesignCreate an AI-first prototyping and contribution framework – design system, AI coding tools, guardrails, automated review and CI – so product managers and designers can prototype and contribute production-grade UIStay hands-on: write a significant share of the critical code, set standards, and pair with and level up our frontend engineersWork with a clear operating split: after architecture-focused first stints, spend around 80% of your time hands-on coding and 20% on architecture, design-system leadership and enablementWhat success looks like After 90 days: frontend audit of both products done, target architecture and migration roadmap agreed, design-system tokens and core components live, and the first prototype built and shipped by a product manager or designer on the new frameworkAfter 12 months: both products run on the shared design system, the frontend rework shows measurable efficiency gains, and product and design prototype independently as a routine – frontend is no longer the bottleneck Your profileMust-have Expert-level React and TypeScript, proven in complex production SaaS frontendsA real AI-first engineering practice: you use AI coding tools and agents daily and have built workflows or frameworks that others use – not just "I use Copilot"Design-system architecture: you've built or led a design system (tokens, component library, Storybook or similar) that was adopted across multiple teams or productsWeb Components (Custom Elements, Shadow DOM, embedding in t