Frontend Developer

Zelh is a fast-growing, passionate outsourcing company.

Our mission is to be the most reliable company by offering and maintaining consistently high-quality services.

We achieve the mission by fostering long-term relationships with customers, employees, and vendors. Personal attention, timely communication, and respect for all people are the basis of our business philosophy!

Now we are looking for Frontend Developer for one of our logistics client.The company is making a SMB version of this TMS and has 60% of it done, but need to finish the project. This will require a code review and clean up, revising the UI for mobile, desktop, Andriod/IOS app, as well as using LLM and Chatbot to build out features.
An ideal candidate will utilize AI agents to support daily coding tasks (e.g., ChatGPT, Claude, Anthropic), and be familiar with LLMs and AI-based projects.

Must-Have (Non-Negotiable)

• 3+ years react development with a portfolio of complex, data-heavy dashboard applications (not just JavaScript, not just “frontend,” React with hooks, context, andcomponent architecture)

• Strong TypeScript (TMS dashboard with AI actions is too complex for untyped JavaScript)

• Experience rebuilding a frontend against an existing backend (need to map to existingAPI contracts they didn’t design)

• Deep experience with state management at scale (Redux, Zustand, React Query, or acombination)

• Strong proficiency with a component library

• Experience building role-based UI (what user can see and do is determined by user type)

• Strong understanding of form architecture in React (complex, multi-field forms withvalidation, conditional fields, and server-side error handling)

• Responsive design that actually works. Simple yet effective (we have most UI designs,but many pages will need to be created)

• Strong understanding of asynchronous UI patterns (loading states, error states,optimistic updates)

Strong Preference

• Experience building dashboard-heavy applicaƟons (data tables, filters, status boards, real-time updates)

• Experience building multiple frontends that share one backend

• Experience with WebSockets or SSE (Server-Sent Events) for real-time data (shipment status updates need to push to the UI without refresh)

• Experience with form-heavy UIs that connect to real business data (load entry, driverassignment, document uploads)

• Experience with data visualization (charts, maps, and status boards for operationalmonitoring)

• Has built file upload and document management UIs (drag and drop, upload progress, preview, and status tracking for documents going through the OCR pipeline)

AI-Specific Requirements

• Has built a web-based streaming chat interface (to handle server-sent events orWebSocket streaming from an LLM API, rendering progressively as tokens arrive)

• Experience designing and building AI action receipt UI (clear, auditable display of what AI did in the system, what data it changed, and a path to review or reverse it)

• Has built OCR review interfaces (AI-extracted fields from a scanned document alongside the original document image, with field-level confidence indicators and editable fields for human correction before commiƫng to the database

• Understands optimistic UI patterns for AI actions (show the expected result of an AIaction immediately while the backend confirms, and handling rollback cleanly if it fails)

• Experience with AI process status UIs (progress indicators, background task monitoring, and notification patterns for long-running AI processes like batch document processing)

Working conditions:

• Working hours: flexible, but with American time overlap

• Working mode — remote/hybrid

• 20 days of PTO, 11 days of National Holidays and 3 sick leaves

• Equipment provided

• Tax coverage