- 23:16:02
- Action received
- 23:16:04
- Payment captured
- 23:16:05
- Ticket accepted
- 23:16:06
- Inventory decremented
- 23:16:07
- Owner record written
This describes how Corvian designs and builds these systems. It is not a study of research participants, and it does not report outcomes for a client.
01What does the customer do?
The action has to be completable by a person standing outside a closed shop at 23:16, on a phone, with one hand. That constraint sets the whole interface: few decisions, no account, a price visible before the commitment, and a state the customer can trust once they let go of the phone.
CONSTRAINT / ONE HAND, ONE MINUTE, NO ACCOUNT
02What validates that action?
An unvalidated action is a liability: it can ask the kitchen to make something nobody paid for, or hold a chair that was never really free. Validation is payment for an order and availability for a booking, and it happens before the operation is told anything at all.
RULE / VALIDATE BEFORE YOU DISPATCH
03Who or what needs to respond?
Someone in the building has to receive work in a form they can act on mid-shift: large, ordered, one state at a time, and safe to touch with flour on their hands. A notification is not a response. A queue with states is.
SURFACE / BUILT FOR A BUSY SHIFT, NOT A DESK
04What must be recorded?
The record is what still exists tomorrow. It has to carry the money, the time, the items, and the state, and it has to be written once so the totals cannot disagree with each other. This is where most stitched-together tools fail quietly.
RECORD / WRITE ONCE, COUNT ANYWHERE
05What does the owner need to see?
Not a dashboard of everything. The owner needs the short list of things that require a decision, and enough history to answer what happened last night. Everything else should stay quiet until it is asked for.
VIEW / DECISIONS FIRST, HISTORY ON DEMAND
FAILURE STATES ARE PART OF THE DESIGN
Payment declines
Nothing reaches the operation. The customer is told immediately and can retry without re-entering the order.
The kitchen is closed
The action is refused at the door rather than accepted and silently dropped. A closed shop should not be able to take an order it cannot fill.
The slot was taken first
The hold fails, the schedule is re-read, and the customer is offered the nearest genuinely free time instead of a confirmation that will have to be undone.
The record write fails
The money and the operational state are never allowed to disagree. The order is not treated as complete until the record exists.