react for agentic AI products

Shelf builds an AI operating system for the enterprise that models company policies, workflows, and operational logic into an AI Data Model. Its platform enables AI agents to reason reliably and deliver precise outcomes at scale, serving enterprise customers with production data and mature integrations.

• Design and ship production Next.js SSR applications with complex state, high-load scenarios, and real-time AI interactions at scale;
• Build interfaces for AI-powered features, including streaming LLM responses, semantic search across millions of documents, interactive knowledge graphs, and agentic builders;
• Architect component libraries and maintain the design system with reusable, accessible, and consistent user experiences;
• Deliver enterprise-grade functionality covering localization, accessibility compliance, cross-browser support, and security;
• Monitor production performance, optimize bundle sizes, instrument Core Web Vitals, and ensure applications scale gracefully after launch;
• Maintain high standards for code quality, testing, and frontend craft through code review and mentorship;
• Turn ambiguous product problems into shipped, well-reasoned interfaces;
• Make complex AI behavior legible and controllable through user interface design;
• Build reusable, accessible, and fast components for enterprise-scale workloads;
• Drive momentum and progress on frontend work.

• Over 5 years of frontend engineering experience, including 3+ years specializing in React and modern TypeScript;
• Production Next.js experience with SSR applications at scale, app router, server components, and SSR, SSG, and CSR trade-offs;
• Experience with complex state management for real-time collaboration, optimistic updates, multi-tenant isolation, and large-scale data synchronization;
• Experience building AI/LLM interfaces such as streaming token responses, chat UIs, or semantic search;
• High-load performance experience, including monitoring and improving Core Web Vitals under heavy traffic and large datasets;
• Experience with enterprise application concerns including localization, accessibility, security, and compliance;
• Security-conscious engineering approach and careful handling of sensitive data;
• Strong product and UX judgment, with the ability to identify issues and propose solutions independently;
• Daily use of AI coding agents and interest in harness engineering;
• Clear verbal and written communication of design decisions and technical trade-offs;
• Nice to have: React Flow, Highcharts or other complex data-visualization libraries, vector search UIs, RAG interfaces, generative UI, Node.js/Python, API design discussions, design systems, open-source component libraries.

• Office role in Warsaw;
• Shelf is building across three hubs: New York, Warsaw, and Lviv.