iQoo

The prompt to build it yourself

Build me a temperature control tool with overrun alerts, for my restaurant, to replace a HACCP subscription.

Stack: installable phone web app (PWA, mobile first), Node, Express, SQLite (better-sqlite3), hosted on my small server. No heavy front-end framework.

Core of the tool:
- Configurable zones and equipment (positive cold room, negative, display case, hot dishes) with minimum and maximum thresholds.
- Entering a reading in two taps; if the value goes outside the threshold, the non-conformity opens automatically.
- Notification (email or ntfy) when a reading is out of range or missing.
- Trend chart per piece of equipment over 7 days.

Common requirements (a reading only counts as evidence if it is reliable):
- Every record is timestamped by the server, with the user. A reading is never edited or erased: a correction creates a new line that points back to the old one (append-only log).
- Deviations (temperature out of range, cleaning not done) trigger a non-conformity to handle: cause, corrective action, closing date.
- Thresholds, zones (cold rooms, hot dishes) and checklists are set in a configuration file, without touching the code.
- PDF export per period, ready to show during a health inspection. Configurable data retention period.
- Several users (PIN code per employee), no email account. No telemetry.
- Simple traceability: products in with batch and use-by date, out into production.

Out of scope: connected probes, several venues, certification.

README: installation, database backup, and a reminder that this tool documents your food safety plan but does not replace it: have it reviewed by your inspection body or a hygiene consultant.