Production planning dashboards

Context

A roof-tile business planned production with a dashboard that had been built quickly by prompting an AI. It showed the right numbers in a demo, but logic, data access and secrets were mixed together in the browser, which made it unsafe and hard to change.

My role

• Main developer of the production rewrite and of a companion make-to-order (MTO) planner, with almost all of the commits in both.

What I built

• An audit of the prototype that sorted every problem by risk, followed by a phased refactor plan the team could track.
• A split into a NestJS API that owns data, business rules, email and AI features, and a Next.js frontend that only renders.
• Monitoring for stock and backorders, production plans, raw-material projection and purchase order rescheduling.
• Single sign-on (SSO) through the company portal, role and user administration, and permission checks on every read endpoint.
• Security hardening: input validation, security headers, a non-root Docker image with health checks, and Excel exports that guard against formula injection.
• An MTO planner on the same architecture, with business rules agreed with the process owner and written down.

Decisions

• Every frontend call goes through one typed API client, so the frontend cannot reach data directly again.
• Write the audit and the plan down first, so the next developer knows why each convention exists.