How it was made
The real working documents behind the build, published in full
Owly Post Cloud was built out of one handover to a coding agent. That sounds like a prompt trick, but the prompt was the shortest part. Everything that made it work sat in the documents written before it: what the product was, what it would never do, how it was structured, and what it was allowed to depend on.
Those documents are below, in full. Not a summary of them, and not something reconstructed afterwards. They are the real artifacts, shortened only where they held operational detail for a live product with paying customers.
How to read them
Start with the spec. It carries the numbered decisions, and almost everything else refers back to them. The agent rules are the shorter and stranger document: the rules of collaboration rather than the product, including when the agent has to stop and ask instead of choose. The kickoff prompt shows what a handover actually looked like, and the decisions log shows what happened every time reality disagreed with the plan.
The four phase reports are the receipts. They record what each round delivered, what deviated, and what was still open, including a phase whose central decision got reversed the day after it was signed off.
The spec
Locked decisions, architecture, data model, phased delivery plan
The agent rules
Seven golden rules, the mandatory gates, the stop rules
The kickoff prompt
One handover in full: requirements, a hard stop, a definition of success
The decisions log
Every judgment call where the spec was silent or wrong, with its reason
What was changed for publication
These are working documents, not a tidied-up version written for an audience. Two things were done to them before they went up.
Operational detail was removed. The runbook and the launch checklist are not here at all, because they hold DNS records, environment inventories, backup mechanics and recovery procedures for a running product. A sandbox price identifier, a webhook signing secret and the exact admin-grant mechanics were taken out of the phase reports, and the summaries around them kept.
The decisions log is a condensed edition. Each entry is shortened to its decision and its reason, and one entry written in Dutch was translated. Entries were shortened, never rewritten: no reasoning has been improved after the fact. Where a phase report describes something that was later superseded, an editor's note says so and points at the entry that replaced it, and the original text is left standing.
The reasoning behind this method
Why any of this exists, and what happens if you skip it, is a separate piece of writing.