A reminder that goes once, with no scheduler
A collection is not a delivery. When a customer forgets a delivery, it turns up anyway. When a customer forgets a collection, a decorated cake sits behind the counter until it is thrown away — and the shop has already paid for the ingredients and the morning.
So the day before, the customer gets a reminder. The interesting part is how, because nothing in a Wix app runs on a timer.
There is no scheduler. So the check happens whenever the app is already awake — a dashboard load, an order arriving — exactly like the retention clean-up. That means it may be asked the same question many times in an hour, so the booking itself records that its reminder went and is never picked up again.
The second half is that the app does not send the message. It cannot send email, and should not try to. What it does is tell the shop’s own Wix Automations that something happened, and the shop’s automation sends whatever they wrote.
That is the right division regardless of the platform constraint. The wording of a message to a customer belongs to the person whose shop it is, in the editor they already know, not buried in an app’s settings behind a developer. A bakery writes to its customers in its own voice, and no setting screen I build will ever capture that as well as a text box they already use.
It also means the customer’s address never leaves their site on our account, which made the privacy policy considerably easier to write honestly.