Full-Stack Developer (FastAPI + React)

**Full-stack developer — review & improve a live SaaS app (FastAPI + React)** I'm looking for an experienced full-stack developer to review my live web app end to end and make improvements as needed — security, code quality, architecture, and integration reliability. Starts as a review-and-improve pass; ongoing work if it goes well. **The app:** a multi-tenant candidate-onboarding SaaS for recruitment agencies, integrated with ATS/CRM (send documents for completion, capture data, e-signatures, sync to/from AtS). It's live with an early client and was originally built with an AI app-builder, so part of the job is bringing it up to a professional, scalable standard. **Tech:** Python/FastAPI (async), MongoDB, React 19, Tailwind. Integrations: Stripe, Resend, AWS S3. **You must have:** - Strong Python/FastAPI and MongoDB - Solid React - Multi-tenant SaaS and secure handling of personal data (GDPR a plus) - Comfortable hardening an existing codebase, not just greenfield - Careful and test-first — the app is live -ATS experience a bonus, not essential **The job:** review the full app, fix priority issues (security and data-isolation first), and advise on scaling. I have an independent code review and tech-stack doc to share once we're working together.