Hot Food Machine AppHot Food Machine App

The problem

Around 500 of the machines in the fleet sell food, restocked and quality-checked every day because what is inside them expires.

• The hot food machines also heat the meal before dispensing it, which turns a sale into a stateful process that takes time: the customer is waiting, the food is already paid for, and the order has to hold through the whole heating cycle.

What I built

I wrote a new machine app for the hot food machines from scratch: the ordering flow, the heating process and hot food dispensing.

What it changed

Because it was written around heating from the start, the app holds each paid order through the cycle and is built to end in a correct state even when the heater, the tray or the network fails part-way through.