Full-Stack Developer (AI-First / Claude Code)

SaaS Platform · React + Fastify · PostgreSQL

About the Project

We’re building a sophisticated AI-powered matching and analytics platform that uses multi-dimensional profiling and advanced algorithms to optimize decision-making.

The product has a validated prototype and real traction. We’re now moving into production hardening and scale, and we’re looking for a senior developer to take ownership of the backend architecture while actively evolving the frontend.

A core part of this role is working AI-first: we expect you to use Claude Code as a primary development tool, not as an experiment or side-assist.

The Role

You’ll design and implement the full production backend for our React-based SaaS platform, replacing mock data with real infrastructure:

• databases
• authentication
• APIs
• AI integrations
• deployment pipelines

You’ll also contribute directly to the frontend where needed.

Claude Code is a hard requirement.

We expect you to be comfortable (or explicitly motivated) to:

• scaffold systems with AI
• refactor and evolve large codebases using AI assistance
• co-design architecture with Claude
• use AI for documentation, tests, migrations, and reasoning

This is an AI-augmented engineering role, not a traditional “write everything by hand” position.

What You’ll Build

Backend Architecture

• Fastify REST API

  High-performance Node.js framework with TypeScript-first design and built-in validation

• Database

  PostgreSQL 15 with Prisma ORM (type-safe queries + automated migrations)

• Authentication & Authorization

  JWT with refresh tokens, httpOnly cookies, and role-based access control

• Caching Layer

  Redis for sessions and performance optimization

• Validation & Types

  Shared Zod schemas between frontend and backend

• API Design

  RESTful endpoints with structured error handling and consistent responses

Infrastructure & DevOps

• Monorepo Setup

  pnpm workspaces separating frontend, backend, and shared packages

• CI/CD

  GitHub Actions with automated tests, security checks, and deployments

• Environments

  Isolated staging and production environments

• Deployment
  • Frontend: Vercel (CDN + edge)
  • Backend: Railway or Supabase (auto-scaling)

• Containerization

  Docker-based local and production environments

Integrations

• OpenAI API

  Document parsing, analysis, and intelligent matching logic

• Email Services

  Resend or SendGrid with template-driven transactional emails

• File Storage

  Secure uploads via Supabase Storage or AWS S3

• Monitoring & Analytics

  Sentry (errors) and PostHog (product analytics)

Testing & Quality

• Backend Testing

  Vitest for unit and integration tests with test databases

• End-to-End Testing

  Playwright covering full user workflows

• Code Quality

  ESLint, Prettier, Husky pre-commit hooks

• API Documentation

  Auto-generated OpenAPI specs from Zod schemas

Required Experience

• 5+ years of professional full-stack development
• Strong experience or strong willingness to work AI-first
• Hands-on experience with Claude Code for real production work
• Advanced React and modern frontend practices (React 19, hooks, Zustand)
• Node.js backend development (Fastify preferred, Express acceptable)
• PostgreSQL schema design, indexing, and performance optimization
• Prisma ORM or similar type-safe database tooling
• RESTful API design with authentication (JWT, OAuth concepts)
• Git-based workflows and CI/CD pipelines
• Testing across the stack (unit, integration, E2E)

Tech Stack

Frontend (Existing)

• React 19, Vite 7, React Router 7
• Ant Design 6, Zustand 5
• React Flow, Recharts, @dnd-kit
• Vitest, Playwright

Backend (Developing)

• Fastify
• PostgreSQL 15 + Prisma
• Redis
• Zod
• JWT authentication
• Helmet (security)

Infrastructure

• pnpm workspaces (monorepo)
• Docker + docker-compose
• GitHub Actions
• Vercel (frontend)
• Railway / Supabase (backend)

Third-Party APIs

• OpenAI GPT-4 API
• Resend / SendGrid
• Supabase Storage
• Sentry

Highly Desirable

• Deep Fastify experience
• Prisma with complex relational schemas
• Monorepo experience (pnpm, Yarn workspaces, Turborepo)
• Production TypeScript at scale
• Ant Design customization
• Docker for both dev and production
• OpenAI / LLM integration experience
• Vercel and Railway deployments
• Database migration strategies
• Strong opinions on AI-assisted development

Required Skills (Experience Level)

• Node.js (Fastify / Express) — 4+ years
• TypeScript — 4+ years
• PostgreSQL (schema design, indexing, optimization) — 3+ years
• Prisma ORM — 2+ years
• React (hooks, functional components) — 3+ years
• Zustand or similar state management — 1+ year
• REST API design & backend architecture — 4+ years
• Authentication (JWT, refresh tokens, RBAC) — 3+ years
• Docker (local & production workflows) — 2+ years
• CI/CD (GitHub Actions or similar) — 2+ years
• Monorepo workflows (pnpm / yarn workspaces) — 1+ year
• Testing (Vitest / Jest / Playwright) — 2+ years
• OpenAI / LLM API integration — 1+ year
• Claude Code (AI-assisted development workflows) — 1+ year