We are building an AI-powered SaaS platform and need a skilled developer to help us finalize the payment, user management, and database system. The core AI functionality is ready — now we need the infrastructure to onboard users, manage subscriptions, and connect payments. Responsibilities Integrate Stripe Checkout / Billing for subscription payments. Build a secure user authentication system (sign up, login, password reset). Create a user database (Postgres, MySQL, or Firebase) to store user profiles, subscription status, and usage data. Link payment status with access control (e.g., restrict features if payment is inactive). Develop a simple homepage / dashboard where users can: Manage their account View subscription status Access the SaaS tool(s) Ensure proper security, data validation, and error handling. Requirements Strong experience in full-stack development (frontend + backend). Proficiency with one or more stacks: Node.js / Express + React / Next.js OR Python / Django / Flask + React / Vue Hands-on experience with Stripe API (Billing, Webhooks, Checkout). Familiarity with databases (Postgres, MySQL, MongoDB, or Firebase). Knowledge of secure authentication (JWT, OAuth, or similar). Ability to write clean, maintainable, and well-documented code. Nice to Have Experience deploying on AWS, Vercel, or DigitalOcean. Background in SaaS or subscription-based products. Understanding of AI/ML API integrations (helpful but not required).