Senior React Frontend Developer / Web Application Engineer

Project overview

For our client from the public sector, we are looking for a Senior React Frontend Developer / Web Application Engineer (m/f/d) starting immediately.

+++Important: Deadline for feedback is Thursday 1 PM+++

Responsibilities

• Frontend Architecture & UI Development: Conception and implementation of highly responsive, modular Single-Page Applications (SPA) or Micro-Frontends based on React and TypeScript.
• Interactive Data Analysis & Visualization: Development of performant user interfaces for the visual representation of complex tax data streams, filter trees, drill-downs, and graph/network analyses (e.g., visualization of supply chains and suspicious transaction patterns).
• Mass Data Display in Frontend: Optimization of rendering performance and memory consumption when displaying extensive datasets (Virtual Scrolling, Infinite Loading, server-side pagination in complex Data Grids).
• Accessibility & Usability: Consistent implementation of legal requirements for accessibility according to BITV 2.0 / WCAG 2.1 (Level AA) and close coordination with UX/UI designers and the VAT Reporting System working group.
• State Management & Interface Connection: Building robust client architectures for asynchronous data retrieval (RESTful APIs, OpenAPI, WebSocket/SSE) and efficient state and cache management.
• Test Automation & Code Quality: Ensuring high test coverage through automated unit, integration, and end-to-end tests (Jest, React Testing Library, Playwright/Cypress).
• Collaborative Teamwork: Active participation in agile processes (Scrum), conducting structured code reviews, and knowledge transfer between developers in Hesse and Lower Saxony.

Requirements

Skills:

• At least 5 years of demonstrable practical experience in professional frontend development with React and TypeScript in an enterprise environment.
• Solid practical experience in state and cache management of modern React applications (e.g., TanStack Query / React Query, Zustand, Redux Toolkit).
• Demonstrable expertise in the performant display of complex table data (e.g., with AG Grid, TanStack Table) including client/server-side filtering, sorting, and grouping.
• Solid knowledge and demonstrable practical experience in accessible web development according to BITV 2.0 / WCAG 2.1 (min. Level AA) and semantic HTML5/WAI-ARIA.
• Confident use of REST APIs, JSON, token-based authentication (OAuth2, OIDC / Keycloak), and knowledge of web security standards (OWASP Top 10, XSS, CSRF, CSP).
• Comprehensive experience with Jest and React Testing Library as well as end-to-end testing (Playwright or Cypress).
• Confident use of modern build tools (Vite, Webpack) and container deployments (Docker/Podman on Kubernetes / OpenShift).
• Fluent German and English, both written and spoken (at least language level C1 in German and B2 in English)
• Data Visualization: Experience with visualization libraries for displaying charts and relational data structures/network graphs (e.g., Apache ECharts, D3.js, React Flow, or Recharts).
• Design Systems & Components: Experience in building or using reusable UI component libraries (Design Systems, Storybook, Tailwind CSS, Material UI).
• Architecture Concepts: Experience with micro-frontend architectures (e.g., Webpack Module Federation) or monorepo structures (Nx, Turborepo).
• Public Sector / KONSENS: Prior experience in public administration projects, KONSENS style guides, or governmental IT systems (especially tax administration/audit software).
• Agile Working: Experience in cross-state or scaled agile development teams (Scrum / SAFe).

Project details

asap

12 months +

Full-time

90% Remote - Frankfurt

+++Willingness to undergo SÜ2 clearance must be given+++

• Start: ab sofort
• Duration: 12 Monate
• Remote: hybrid
• Location: Frankfurt, Deutschland, DE
• Languages: German