Non-developers are shipping working software now. A marketing lead builds an internal tool over a weekend, a founder ships a prototype that gets customers, a researcher writes the script the whole lab depends on. Then the tool has to be dependable, and someone has to make it so. That someone is increasingly going to be you, and the job is not "rewrite it." The job is to move it up a scale without losing what already works.

I think of projects as doghouses, cabins, and skyscrapers. A doghouse is small, casual, and shipped in a weekend, which is the vibe coding sweet spot. A cabin is modest but dependable, with a testable core and explicit boundaries. A skyscraper adds coordination, review gates, and CI discipline because other people have to work inside it. Most inherited vibe-coded projects need to become cabins, and the mistake in both directions is expensive. Build a doghouse like a skyscraper and you never finish. Run a skyscraper like a doghouse and it fails in ways that cost real money.

This session walks the doghouse-to-cabin transition on two real projects using Claude Code. A single-file JavaScript app that a request for tests forces into a testable core with boring DOM glue. A Spring Boot certificate service that started as a joke and ended with property-based tests on its cryptography. Along the way we do the read-only orientation pass that makes the agent mark where it is guessing, write the project memory that stops the next session from re-learning everything, decide what actually needs a test, and catch the failures that come with the territory. Tests the agent rewrote until they passed. A confident architecture map that disagreed with the code. A refactor that quietly changed behavior.

You'll leave with a triage sequence for any inherited agent-written codebase, the prompts that drive each step, a rule for knowing when to stop, and a public repository showing both projects before and after.

50-minute talk. Intermediate. One example is vanilla JavaScript, the other is Java and Spring Boot, so no framework knowledge is assumed. Material drawn from my forthcoming O'Reilly book, Claude Code: Up and Running.