I’m looking for a senior full-stack developer to help me build a private, action-capable AI platform that integrates with business systems such as BigChange, Outlook (Microsoft Graph), Google Drive, and later Xero, using OpenAI as a reasoning engine.
This is not a chatbot or prompt-engineering project. It’s a secure internal SaaS-style system with real write access to APIs.
What the platform will do
Chat-style interface (similar to ChatGPT)
Secure user login and role-based permissions
Interpret user intent via OpenAI
Execute validated actions via APIs (e.g. create purchase orders in BigChange)
Read/write data to external systems (BigChange required, Xero later)
Store knowledge and precedent in a vector database
Allow file uploads and document ingestion
Full audit logging and approval workflows
Designed to be extended and improved over time
Required experience (non-negotiable)
Senior full-stack development experience (5+ years)
Strong API integration experience (REST, OAuth, webhooks)
Experience with OpenAI / LLM APIs in production systems
Clear understanding of secure backend architecture
Experience building SaaS platforms or internal tools
Comfortable designing systems where AI plans but backend executes
Preferred tech stack (flexible but indicative)
Frontend: React / Next.js
Backend: Python (FastAPI) or Node.js (NestJS)
Databases: PostgreSQL, Redis
Vector DB: Pinecone / Qdrant / Weaviate
Auth: OAuth / JWT
Cloud: AWS / GCP / Azure
Very important
OpenAI must not hold API keys or perform actions directly
All actions must be validated and executed by the backend
Accuracy, safety, and auditability matter more than speed
Nice to have
Microsoft Graph API experience
Accounting or FM system integrations
Experience building approval workflows
Product-minded approach (not just coding to spec)
Engagement
Initial build: 6–8 weeks
Ongoing improvement work expected
Looking for someone I can work with long-term
Please do not apply if you only build chatbots, landing pages, or no-code automations.
