Contrast Revival

The Problem

A small business had an online booking system and a smart lock on their premises — but the two couldn't talk to each other. Every booking required someone to manually grant access, which meant staff had to be on-site during operating hours just to let customers in. It limited when the business could operate and how many bookings they could take.

The Solution

I built an app that connects the booking system to the smart lock on the premises. When a customer books, the system automatically generates a time-limited access code for the door and emails it ahead of their appointment — no manual steps, no staff involvement.

The Impact

The business moved to a fully self-service model — no staff needed on-site to let customers in. This opened up longer operating hours and increased booking capacity without any additional overhead. Deployed on Azure Container Apps with auto-scaling, the entire system runs for approximately £5 per month, making the move to self-service practically cost-free.