Senior Software Developer to Assist in Vibe-Coded Software Hardening and Stripe Integration.

I’m looking for an experienced full-stack developer to help polish and production-harden an existing web app before public launch. The app is already deployed with a React/Vite frontend, Node/Express backend, Supabase Auth/Postgres, Render, and Vercel. Main tasks include improving edge-case handling, tightening basic security/auth flows, cleaning up deployment issues, fixing any user-flow bugs, and integrating Stripe for subscriptions/payments. This is not a full rebuild. I need someone practical who can review the existing codebase, make targeted improvements, and help get the product stable enough for real users. Ideal experience: React/Vite, Node/Express, Supabase, Stripe, deployment/debugging on Vercel/Render, and production-readiness/security best practices.