Grocery App Technical Blueprint

I’m putting together a complete blueprint for a full-scale grocery delivery platform and need a seasoned technical writer or software architect to turn the vision into a clear, developer-ready document.

Scope of the write-up
• System overview, high-level architecture, and technology stack recommendations
• End-to-end user flows, with priority on Customer, Administrator, and Delivery-management journeys
• Deep dives into Payment processing, Order placement & tracking, and Notifications & user-account logic
• Product catalog, inventory rules, shopping cart, checkout, delivery assignment, and admin reporting
• Normalized database schema, ER diagrams, and key entity descriptions
• REST/GraphQL API specs: endpoints, request/response models, auth, and error handling
• Security, performance, scalability, and deployment considerations, supported by architecture diagrams and flowcharts

Deliverables
1. Well-structured documentation supplied in BOTH Markdown (for repo inclusion) and a polished PDF (for stakeholders).
2. Editable diagrams (draw.io, Lucidchart, or similar) embedded and provided separately.
3. A concise change-log / version table so future teams can extend the doc.

Acceptance criteria
• All priority flows and features mapped with sequence diagrams or flowcharts.
• DB schema aligns with the described APIs and use cases.
• No section left “TBD”—every bullet above must be addressed with actionable detail.

If you have a track record of producing software design docs that developers can code from, I’d love to see a sample.