Tech Lead

Job Title: .Net Backend Developer with React
Location: Cupertino, CA
Onsite only
Salary-$140k with benefits.
Pay Rate-$55/hr on c2c

JD: Build and extend features in a React 19 SPA using MUI v9, Redux Toolkit and RTK Query: dashboards, data-heavy tables, multi-step workflows, admin and analytics views.
Write RTK Query endpoints against a FastAPI backend, following agreed API contracts: cache tags, invalidation, Eligible to workimistic updates, and correct loading, empty and error states.
Work on the streaming AI chat UI: parsing Server-Sent Events over fetch/Readable Stream, rendering markdown live, showing tool-call progress, retry/backoff and conversation management.
Keep large lists and tables fast with virtualization, memoization and careful render control.
Extend a block-based content editor (drag-and-drop with @dnd-kit, a Monaco code editor, draft publish flows, version history).
Keep security boundaries intact: sanitized markdown (DOMPurify), and sandboxed iframes for untrusted or AI-generated HTML/JS (an opaque origin with no allow-same-origin).
Write Vitest React Testing Library tests with every change, and keep ESLint at zero warnings.
Work with backend engineers on API contracts for features that span both codebases.
pdf.js, Monaco Editor, Recharts or D3.
Streaming UIs (SSE or WebSockets), especially LLM or chat interfaces.
Rich-text or block editors, and drag-and-drop libraries.
Enterprise SSO flows (OIDC, Kerberos/SPNEGO) seen from the frontend.
Comfortable using AI coding assistants (e.g. Claude Code) as part of the workflow.