Backend API Developer — Node.js / Fastify / TypeScript / PostgreSQL

We are building a next-generation vehicle marketplace but with real-time auctions, live mechanic tracking, AI-powered search, and a built-in wallet). We are assembling a small team of specialized contractors and looking for a strong backend developer to own the core API. What you will build: OTP-based phone authentication with Redis-backed rate limiting Vehicle listing CRUD with image upload (AWS S3) and Algolia search sync Real-time auction bidding via Socket.io Buyer-seller chat system Wallet — balance, top-ups, and payouts Role-based access control (Buyer / Dealer / Admin) Audit logging on all sensitive actions Unit tests for all endpoints Tech stack: Fastify 4 · TypeScript · PostgreSQL 15 · Prisma ORM · Redis · Socket.io · AWS S3 · Algolia · JWT You must have: 3+ years Node.js backend experience Must have worked with Fastify or NestJS (Express-only profiles will not be considered) Strong TypeScript — interfaces, generics, proper typing Prisma ORM + PostgreSQL migrations Redis for caching and rate limiting JWT authentication flows Engagement: Duration: 10–12 weeks Budget: $1,400–$1,800 fixed price (milestone-based, 4 milestones) Milestone 1 (20%): First working endpoints delivered and tested Milestone 2 (40%): Core module complete and functional Milestone 3 (30%): Integration testing passed, security review signed off Final 10%: Handover, documentation, and code review complete How it works: NDA signed via Upwork before any files are shared. You receive your scoped contractor package (your module only — not the full codebase). GitHub access granted to your private branch. 30-min kickoff call, then weekly check-ins. To apply, please share: (1) a link to a live API or GitHub repo you built with Node.js/TypeScript, and (2) your experience with Fastify or NestJS specifically.