Full Stack Developer Contract

Client of Talentmate

The project requires an experienced freelance developer to resolve critical authentication and authorization failures and complete core AI and payments functionality for a web-based divination platform built with Next.js and React. The immediate priorities are restoring a functioning admin permission system so dashboard access is reliable, finishing integration with the OpenAI Assistant API to deliver personalized readings, and implementing a secure checkout flow supporting Stripe and PayPal. The codebase uses Supabase for backend services and authentication and is hosted on Vercel; some components (notably the shopping cart) may need to be rebuilt rather than patched. A fresh start for authentication/data is acceptable. The engagement is remote, short-term, and outcome-driven with the expectation of thorough testing and deployment-ready deliverables.

Deliverables

• Fix authentication and permission flows so admin users can reliably access the dashboard and role-based permissions map correctly across the site (Supabase auth integration, JWT/session handling, routes protection).
• Audit and repair or replace the existing cart implementation: restore add/update/remove item behavior, persistent cart state, and correct pricing calculations. Provide unit/integration tests for core cart flows.
• Finish integration of the OpenAI Assistant API for personalized readings: implement conversation/session management, ensure safe prompt handling, support user-specific context, and integrate the assistant responses into the UI with graceful error handling and rate-limit awareness.
• Implement checkout flow supporting both Stripe (recommended: Stripe Checkout or Payment Intents API) and PayPal (smart payment buttons or REST integration), with server-side order creation, webhook handling, and order state persisted to Supabase. Include basic receipt/invoice generation and transactional email hooks (or clear instructions for plugging in an email provider).
• Deploy all fixes to the Vercel environment and verify environment variables/secrets are configured securely. Provide a clear deployment checklist and rollback instructions.
• Deliver final production-ready code, documentation for setup and maintenance (README, env variables, migration steps), and a short handover demo recording (screen-share walkthrough) showing admin login, a sample reading via the Assistant, and a complete checkout flow.

Requirements

• Proven experience with Next.js and React in production applications and practical knowledge of server-side rendering (SSR) and API routes.
• Hands-on experience with Supabase authentication, policies (RLS), and common pitfalls in role-based access control.
• Demonstrable experience integrating OpenAI APIs, preferably the Assistant API or similar conversational endpoints, including safe prompt design and session handling.
• Experience implementing Stripe and PayPal payments (server-side and client-side integration), webhooks, and basic fraud/error handling.
• Familiarity with v0.app or comparable AI integration frameworks is required.
• Comfortable working with Vercel deployments and environment configuration.
• Ability to start immediately and deliver production-ready fixes and features by the requested timeline (target delivery dates to be coordinated with the project owner).
• Strong communication skills, timely updates, and willingness to provide short technical documentation and a demo on completion.
• Mid-level to senior technical competency; portfolio or references for similar projects preferred.

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