Senior Full-Stack Developer for Secure AI-Powered Consumer SaaS

Looking for a senior full-stack developer or small experienced team to build V1 of a secure consumer SaaS platform focused on personal organization, succession, document intelligence, and trusted access. Scope includes both the public-facing marketing website and the authenticated web application. Core V1 includes: Secure user accounts and MFA Private document vault AI-assisted document classification and data extraction Structured organizer for financial, legal, property, insurance, personal, and digital information People/role management with primary and backup successors Successor readiness and confirmation workflows Permission-based trusted access Estate/document review engine with structured findings and scoring Dashboard and ongoing guidance Stripe billing Basic admin/testing tools Preferred stack: Next.js / TypeScript PostgreSQL / Supabase Vercel OpenAI API Stripe Security and permissions are critical because the platform will handle sensitive personal, financial, and legal information. We prefer one strong senior developer or a very small team over a large agency. Please include: Relevant SaaS projects you personally built Experience with secure document storage and complex permissions Experience with AI/LLM document workflows Proposed architecture Fixed-price or milestone-based estimate Estimated timeline What you see as the biggest technical risk A detailed product specification will be provided to qualified finalists.