Senior Frontend React Developer

As a Frontend Engineer at Shelf, you’ll craft the interfaces that make enterprise AI accessible and trustworthy. While others are building chatbots, we’re solving the harder problem: how do you build UIs that help users confidently navigate AI-powered systems processing millions of documents, while maintaining enterprise-grade reliability?

You won’t just build React components — you’ll architect production-ready Next.js applications that handle high-load scenarios with complex states, real-time AI streaming, and multiple layers of enterprise functionality. Every interface decision you make directly impacts how knowledge workers at the biggest companies in the market interact with their most critical information.

This is frontend engineering at its most demanding. You’ll tackle challenges like building real-time streaming interfaces for LLM responses, architecting state management for concurrent AI operations across multiple tenants, creating accessible interfaces for complex knowledge graphs with thousands of nodes, and ensuring blazing fast interactions even with petabytes of searchable content. Your components will bridge everything from enterprise authentication systems to cutting-edge AI models, requiring both sophisticated technical skills and sharp product instincts.

We obsess over frontend quality because we’re building the trust layer for AI itself. When your interfaces gracefully handle edge cases, provide clear feedback during AI processing, and remain performant under load, you’re not just meeting UX standards — you’re directly enabling users to trust AI-powered answers and make critical business decisions with confidence.

You’ll work on production SSR applications serving thousands of enterprise users, implementing localization for global markets, ensuring accessibility compliance, and maintaining security standards that pass SOC 2 audits. Your code will integrate with our Elasticsearch clusters, DynamoDB tables, and Aurora PostgreSQL databases through the largest park of REST APIs, handling real-time websocket updates for AI streaming and collaborative features.

We’re a product company that ships fast without compromising on lasting quality. You’ll work alongside proactive, ever-learning engineers who actively use AI coding assistants (OpenAI Codex, Claude Code) to accelerate development. We build custom MCP servers, implement DSPy pipelines for LLM optimization, and experiment with different AI tools for implementation. In our environment, AI isn’t just what we build — it’s how we build.

The best engineers we know are drawn to problems that matter. If you’re excited by the challenge of building interfaces that make the AI revolution actually usable and trustworthy for enterprise users, this role offers the rare combination of technical depth, meaningful impact, and the prestige of solving UX patterns that the industry hasn’t figured out yet.

Responsibilities

• Design and implement production-ready Next.js SSR applications with complex state management, handling 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, intelligent content recommendations, and AI agentic builders

• Architect component libraries and maintain our design system in Storybook, ensuring reusability, accessibility, and consistent UX patterns across the platform

• Develop enterprise-grade functionality including multi-language support, accessibility compliance, cross-browser compatibility, and security implementations that meet SOC 2 standards

• Create comprehensive technical specifications and component API designs that clearly communicate interface decisions, performance trade-offs, and accessibility considerations

• Build and optimize data-heavy UIs using React Flow for node-based graphs, Highcharts for analytics visualizations, and custom virtualization for handling large datasets

• Instrument components for performance monitoring, track Core Web Vitals, implement error boundaries, and build automated visual regression tests with Playwright

• Take full ownership of the features you build, monitoring their performance in production, optimizing bundle sizes, and ensuring they scale gracefully as user load grows

• Work with SWR for intelligent data fetching, caching, and revalidation strategies that minimize API calls while keeping UIs responsive and data fresh

• Integrate with backend services via REST APIs, handle websocket connections for real-time updates, and implement optimistic UI patterns for seamless user experiences

• Leverage AI coding assistants to accelerate development while maintaining high code quality, and contribute to building internal AI agents that automate frontend workflows

• Stay current with React ecosystem best practices, Next.js updates, AI UX patterns, and modern frontend architecture—experiment with new approaches and share findings with the team

• Contribute to our engineering standards and practices through thoughtful code reviews, mentor colleagues on frontend best practices, and actively participate in our culture of continuous learning

Requirements

• Over 5 years of professional frontend engineering experience, including more than 3 years specializing in React and modern JavaScript/TypeScript

• Production Next.js experience — you’ve built and shipped SSR applications at scale, understand app router patterns, server components, and the trade-offs between SSR, SSG, and CSR

• Deep TypeScript expertise — you write type-safe code with generics, utility types, and advanced patterns.

• Complex state management — hands-on experience architecting state solutions for challenging scenarios: real-time collaboration, optimistic updates, multi-tenant data isolation, and large-scale data synchronization

• Enterprise application development — you’ve built applications with localization (i18n), accessibility, security best practices, and compliance requirements. You understand the complexity beyond “making it work”

• AI/LLM interface experience — you’ve built interfaces for AI-powered features: streaming token responses, chat UIs, semantic search, or similar real-time AI interactions

• High-load optimization — proven track record optimizing applications for performance under heavy traffic, large datasets, and concurrent operations. You monitor Core Web Vitals and know how to improve them

• Modern CSS mastery — strong expertise with Tailwind CSS and/or CSS-in-JS solutions. You can implement pixel-perfect designs while maintaining responsive layouts and dark mode support

• Write well-structured, testable code with thoughtful component abstractions and clean APIs. You know when to abstract and when to keep it simple

• Strong problem-solving skills and genuine curiosity — you don’t wait for designs to be perfect but proactively identify UX issues and propose solutions. You’re never satisfied with “good enough” and constantly refine your craft

• Experience with AI coding assistants (OpenAI Codex, Claude, etc.) and eagerness to push the boundaries of AI-assisted development. Part of this role involves creating AI agents to automate portions of the frontend workflow

• Familiarity with observability and monitoring tools like Datadog, Sentry, or similar platforms for tracking frontend performance and errors in production

• Upper-Intermediate or better English skills for technical communication, documentation, and collaborating with distributed teams

• Present your work effectively both verbally and visually — you can articulate design decisions, create component documentation, and explain technical trade-offs clearly

Be a Plus:

• Experience with React Flow, Highcharts, or other complex data visualization libraries

• Understanding of Node.js/Python/backend fundamentals — you can read backend code and contribute to API design discussions

• Experience with SWR, React Query, or similar data fetching libraries

• Hands-on experience with vector search UIs, RAG interfaces, or semantic search implementations

• Familiarity with MCP (Model Context Protocol), DSPy, or other cutting-edge AI frameworks

• Experience with monorepo tools (Lerna, Turborepo, Nx) and managing shared component libraries

• AWS services knowledge (S3, CloudFront, Lambda) and understanding of serverless architectures

• Built or contributed to design systems or open-source component libraries

• Experience with Playwright, Puppeteer, or Cypress for comprehensive E2E testing

• Experience building AI agent interfaces or agentic AI workflows

What Shelf Offers:

• B2B contract

• Company Stock Options

• Hardware: MacBook Pro

• Modern technical stack. Develop open-source software

• Premier AI development environment: GitHub Copilot, Claude Code, OpenAI Codex, TypingMind, v0, MCP Servers, plus credits for experimenting with emerging AI tools

Why Shelf

• GenAI will be at least a $18 Trillion market by 2032 and Shelf is a core infrastructure that enables GenAI to be deployed at scale

• We are blazing the path for the future of Artificial Intelligence globally.

• Our Leadership Team has deep AI domain expertise and enterprise SaaS background to execute this plan

• We love our customers and our customers love us. Ask a Shelf customer why, and they’ll tell you it’s because of our innovative capabilities, rock-solid reliability, they truly enjoy working with our people, but most of all — it’s the improvements they see in their business KPIs.

• We have raised over $60 million in funding and our investors include; Insight Partners, Tiger Global, Base10, and others

• We have high velocity growth powered by the most innovative product in our category

• We now have over 100 employees in multiple U.S. states and European countries, and we have ambitious hiring goals over the next few quarters.