Full-Stack Developer – AI SaaS Platforms (React / Node.js / OpenAI)

About the Role

We are a Sydney-based software development agency looking for a skilled full-stack developer to take end-to-end ownership of AI-powered SaaS platforms we are building for clients. You will be working across AI projects including multi-provider orchestration pipelines, RAG-based content generation, programmatic document processing, and full multi-tenant SaaS builds. Detailed specifications are ready to go. You will be the primary developer, working directly with our technical lead and project manager.

This is a remote, exclusive role. You must be available during Australian Eastern Standard Time (AEST/AEDT) business hours.

The Work

You will be building full SaaS applications from scratch using React 18, Node.js, PostgreSQL, and TypeScript. The projects are heavily AI-integrated and involve real technical complexity — this is not a CRUD app role.

AI Orchestration and Multi-Provider Pipelines
Work includes building custom orchestration layers that chain multiple AI providers in sequence (including OpenAI, Claude, and Perplexity). You will implement pipeline logic covering parallelism, retry strategies with exponential backoff, rate limit management across providers, and streaming responses via SSE.

RAG and Vector Store Architecture
Projects include work with the OpenAI Responses API, file_search, and managed vector stores to generate AI content grounded in client knowledge bases. The retrieval architecture uses a multi-store design separating shared expert knowledge from per-client and per-job data — shaped by the two-vector-store-per-call constraint on the Responses API. You will build setup scripts, sync logic, metadata filtering, and the full generation pipeline.

Document Processing and Assembly
Work includes parsing uploaded PDF and DOCX files using Azure Document Intelligence to extract questions, tables, and document structure, then mapping AI-generated content back into the original document format without breaking layout or formatting. This is among the most technically demanding work in the engagement and a key competitive differentiator for our clients.

SaaS Platform Features
Projects involve full multi-tenant SaaS applications including user authentication, subscription billing via Stripe and/or Chargebee (webhooks, billing portal, feature gating by tier), knowledge base management, file uploads, admin portals, and health check engines.

What You Will Be Doing

Building AI-powered SaaS platforms end-to-end from detailed functional and technical specifications
Implementing multi-provider AI orchestration pipelines with parallelism, retry logic, and rate limit management
Setting up and managing OpenAI vector stores: file sync scripts, metadata attributes, multi-store retrieval architecture
Solving document mapping challenges: parsing input documents with Azure Document Intelligence and assembling correctly formatted DOCX outputs from AI-generated content
Building full SaaS platform features: auth, subscription billing, multi-tenancy, feature gating, file uploads, admin workflows
Writing production-quality, well-typed TypeScript across frontend and backend
Reading and building from specification documents — raising questions where specs are ambiguous or incomplete
Participating in standups, providing regular progress updates, and communicating blockers early

Requirements

Must Have

5+ years of professional full-stack development with React and Node.js as your primary stack
Strong TypeScript across frontend and backend — comfortable with type inference, generics, and type-safe ORM usage
PostgreSQL with a modern ORM (Drizzle preferred, Prisma acceptable) — schema design, migrations, query optimisation
Solid third-party API integration experience — authentication, webhooks, error handling
OpenAI API experience, ideally the Responses API, file_search, and vector store management; if not, you must be a fast learner from documentation
Azure Document Intelligence
Experience parsing or generating documents programmatically (PDF, DOCX) — extracting structured data from unstructured sources or producing formatted output from code
Stripe integration experience — subscription billing, webhooks, billing portal
Ability to work independently from detailed specifications without needing hand-holding on every decision

How to Apply

Please include the following in your application:

A brief summary of your relevant experience, specifically addressing the AI and document processing requirements
A PDF or Google Doc link to your CV — applications without a CV will not be considered
Links to projects or repositories that demonstrate your full-stack work (GitHub, portfolio, or live projects)
Confirmation that you are: OK with screenshot capture software for time tracking; available during Sydney (AEST/AEDT) business hours; happy in an exclusive role with no paid or unpaid freelance work on the side; and willing to undergo a live technical assessment as part of the interview process