Senior Next.js/React/TS Frontend Integration Engineer (Auth0, tRPC, REST Dashboard)

PROJECT OVERVIEW Center AI Vision is an existing authenticated web platform for GPU Compute and Bitcoin Mining Hosting, with a production-focused roadmap. This is NOT a greenfield build and NOT a pure Figma-to-code task. The platform already includes: - Next.js / React / TypeScript / Tailwind CSS frontend - Completed Figma designs and an existing design system - Protected Investor and Admin areas - Auth0-based authentication (OIDC) with RBAC patterns - Backend services and REST/tRPC integration patterns - GitLab repository workflow with feature branches and merge requests We are looking for a Senior Frontend Integration Engineer who can work INSIDE the existing codebase and deliver production-ready features. This is not a redesign and not a separate app build. CURRENT CHALLENGE The project is delayed because frontend-backend integration and production readiness are not yet stable enough. Specifically: - Auth0 protected routes and RBAC behavior need hardening - Live REST/tRPC API data is not consistently wired into dashboard components - Dashboard state handling (loading, empty, error, unauthorized) is incomplete - Responsive QA for desktop and mobile needs tightening - Overall production readiness (tests, documentation, Git discipline) must improve We need a senior engineer who understands integration in an existing production app, can debug and extend current patterns, and can deliver working, tested features via clean GitLab merge requests. BUDGET AND ENGAGEMENT STRUCTURE (READ CAREFULLY) - Total available budget: USD 1,500 (including trial). - Phase 1 - Paid technical micro-trial: USD 100 fixed-price, scoped task (see below), timeframe 24-48 hours after access is provided. - Phase 2 - Continuation contract (optional): up to USD 1,400 total, split into controlled fixed-price milestones. Continuation is NOT guaranteed. It depends entirely on successful trial delivery and overall performance. The full USD 1,500 is not immediately available without trial review. You must confirm you are comfortable with this structure: USD 100 paid trial, then up to USD 1,400 continuation only if the trial passes. ROLE RESPONSIBILITIES - Work inside the existing Next.js / React / TypeScript / Tailwind CSS application - Implement and fine-tune Investor and Admin dashboard sections - Connect frontend components to real backend / tRPC / REST API data, following existing patterns - Preserve Auth0 login, session handling, RBAC route protection, and OIDC flows - Remove or isolate hard-coded or mock production data in final implementations - Add and verify loading, empty, error, and unauthorized states - Maintain and confirm responsive layouts for desktop and mobile - Follow the existing Figma designs and design system (no redesign) - Work with GitLab feature branches and merge requests using a clean workflow - Add basic automated tests for critical flows - Provide technical notes and Loom walkthroughs explaining your changes WHAT THIS ROLE IS NOT - Not a separate app build - Not a redesign of the product - Not only static Figma-to-code slicing - Not a backend-only role - Not a mobile app task - Not an AI-agent build task - Not a crypto/tokenization task REQUIRED SKILLS - Next.js - React - TypeScript - Tailwind CSS - Auth0 / OIDC and protected routes - RBAC and role-based UI rendering - REST API integration - tRPC (or ability to follow and extend existing tRPC patterns) - GitLab feature branches and merge requests - Automated testing for React/Next.js - Responsive dashboard UI - Production QA - Clear technical documentation NICE-TO-HAVE SKILLS - Playwright - React Testing Library - OpenAPI - TanStack Query / React Query - Vercel preview deployments - SaaS dashboards - Fintech/admin portals - Infrastructure platforms - Authenticated multi-role portals PAID MICRO-TRIAL TASK (USD 100) Scope: Active Allocation Register inside the existing protected Investor area. Timeframe: 24-48 hours after access is provided. Requirements: - Work inside the existing Next.js application only - Use a feature branch (no direct commits to main) - Preserve Auth0 protected route behavior and RBAC logic - Connect the Active Allocation Register to live backend / tRPC / REST API data where available - If any endpoint or data is blocked, document the blocker clearly and follow existing integration patterns - Do NOT use hard-coded production data in the final implementation - Add and verify loading, empty, error, and unauthorized states - Confirm responsive behavior for desktop and mobile - Do NOT create a duplicate app, duplicate dashboard, or public /portal route - Do NOT build the full Allocation Detail module unless the route already exists and only needs simple connection - If View All or View routes already exist, connect them; if they do not, leave clean placeholder actions and document the required route/API DEFINITION OF DONE - GitLab merge request - Branch name - Exact commit hash - Changed-file list - Build/test result - Short technical summary - Backend/API blockers, if any - Confirmation that no secrets are committed - Loom walkthrough showing: (1) login/protected flow, (2) implemented Active Allocation Register section, (3) live API/tRPC data or clearly documented API blocker, (4) loading, empty, error, and unauthorized states, (5) desktop and mobile view TESTING REQUIREMENT (MINIMUM) - 1 API-success test - 1 API-failure test - 1 protected-route or unauthorized-state test SELECTION PROCESS We are running the same USD 100 trial with multiple shortlisted candidates in parallel. The strongest candidate may receive the USD 1,400 continuation contract under fixed milestones. We will select based on working code, code quality, integration discipline, Git workflow, testing, and communication. Agencies are discouraged unless they can guarantee a single named senior engineer who personally writes the code and remains assigned. APPLICATION QUESTIONS (ANSWER ALL) 1. Share one production Next.js / React / TypeScript project you personally built or maintained. 2. Have you personally implemented Auth0/OIDC login and protected Next.js routes? 3. Have you implemented RBAC or role-based UI rendering? 4. Have you connected dashboards to real REST APIs or tRPC APIs? 5. What testing tools do you use for React/Next.js? 6. Are you comfortable working inside an existing codebase without creating a separate app? 7. Are you comfortable submitting GitLab merge requests with commit hash, technical note, and Loom? 8. Are you available to complete the USD 100 trial within 24 to 48 hours? 9. Will you personally write the code? 10. Are you comfortable with the budget structure: USD 100 paid trial, then USD 1,400 continuation only if the trial passes? ADDITIONAL TERMS All communication, contracts, and payments must remain strictly through Upwork. Do not ask to move communication off Upwork or share email before the Upwork contract is active. Please do not request private repository links, credentials, Auth0 secrets, or API keys in your proposal. We are NOT looking for junior developers, pure Figma-to-code developers, agencies that cannot guarantee the assigned coder, or candidates who want to rebuild from scratch. To confirm you read this carefully, start your proposal with: "Center AI Vision - Senior Integration" and then answer all ten application questions.