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

FACT-Finder; Berlin; Hybrid; EUR 120,000 - 180,000; Full time

Job summary

FACT-Finder is building the AI-first frontend platform and design system to unify two React frontends into a single, efficient system. You will own the shared design system, mentor frontend engineers and drive architecture across products.

Based in Berlin with hybrid work options, 2–3 office days per week, you will ship production-grade UI and prototype features with AI tooling, while maintaining hands-on coding and setting technical direction at Staff/Architect level.

Qualifications

• Expert-level React and TypeScript in complex production SaaS frontends.
• AI-first engineering practice using AI coding tools and agents daily.
• Designed or led a design system with tokens and a component library adopted across teams.
• Experience modernizing or migrating frontend stacks and working with Web Components.

Responsibilities

• Define and drive the target frontend architecture across both React products - one consistent, efficient system.
• Build and own our shared design system: tokens, component library and Web Components for embeddable shop UI.
• Create an AI-first prototyping framework - design system, AI tooling, guardrails, CI for production-grade UI.
• Stay hands-on: write a significant share of critical code and mentor frontend engineers.
• After initial phases, spend ~80% on coding and ~20% on architecture and enablement.

Skills

Expert-level React

TypeScript proficiency

AI-first engineering practice

Design-system architecture

Frontend architecture leadership

Hands-on coding

Business-fluent English

Tools

Storybook

Web Components

AI tooling (Claude Code, Cursor)

Design tokens

Job description

Introduction

Teaser 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 reports
• Reporting line: VP Engineering. Executive sponsor: our CPTO
• Products: 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 design
• Location: Berlin; Munich, Pforzheim or Stockholm possible - hybrid with 2–3 office days per week; occasional travel (<10%) for offsites and design-system workshops
• 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 mission

What you'll do

• Define and drive the target frontend architecture across both React products - one consistent, efficient React-based system, migrated step by step
• Build and own our shared design system: tokens, component library and Web Components for embeddable shop UI, tightly aligned with Product Design
• Create 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 UI
• Stay hands-on: write a significant share of the critical code, set standards, and pair with and level up our frontend engineers
• Work 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 enablement

What 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 framework
• After 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 profile

Must-have

• Expert-level React and TypeScript, proven in complex production SaaS frontends
• A 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 products
• Web Components (Custom Elements, Shadow DOM, embedding in third-party environments) plus a frontend architecture track record: you've modernized or migrated a frontend stack at least once, ideally several times
• 6+ years in frontend or software engineering, including 3+ years at Staff, Lead or Architect level - setting technical direction across teams, not just within your own
• Hands-on today: you write production code yourself - this is not a concept-only architect position
• Business-fluent English (C1); no formal degree required, your track record counts

Nice-to-have

• Technical leadership without line management: you've led a SaaS frontend team through a major technology change
• Meta-frameworks such as Next.js and/or Astro - and a clear view on when to use which
• Design-to-code and prototyping tooling: Figma workflows, design-token pipelines, AI UI generation (v0, Claude Code, Cursor, MCP-based tooling)
• eCommerce, search or product discovery frontends (search UIs, embeddable shop widgets)
• React on non-JavaScript backends (Java/Spring, .NET); Fable/Feliz or Ant Design