About

I do not write the code. The AI does. I have spent twelve years finding where it breaks.

What the job actually is

QA. Formally “quality assurance”; in practice:

Trying to break the thing that was made.

Build a game or an app and something in it is certainly wrong. Finding that before release is the job.

And the core of this work is not hands but instinct — recognising “that looks suspicious.” There is never time to press everything.

So why build things when the AI writes the code

Because the instinct for where things break works regardless of who wrote the code.

Human-written or machine-written, the places that break are similar — boundary values, things happening at once, undoing, and the place you assumed could not happen.

Which makes the split look like this:

Who	What
The AI	Writes the code
Me	Decides what to build, points at where it will break, and confirms whether it did

How the work runs these days

I set it going at night and go to sleep. In the morning sixteen things are finished.

That works not because it is well built but because it is built not to stop. One failure does not take the rest with it.

What is here

Four things — tools I built, teardowns, writing, and today’s AI news.

What is not here

My day job.

The QA automation I built for a living is several times the size of this list. And it belongs to the company, not to me.

The omission is stated on the page. Without that, this list reads as everything I have done.

Why write any of it down

Twelve years in QA teaches this:

Don’t record a verdict and you will make the same verdict again.

And I was badly caught by it once. Something I had already researched and concluded, I researched again from scratch months later.

So I pulled every link out of two years of working records and turned them into a searchable index. The teardowns on this site come out of that index.

Getting in touch

The repository link is at the bottom left.

If you are actually going to use any of this, filing a question there is the fastest route.

The detailed record starts here

Moon Hyeonggeun. Twelve years in QA.

I don’t write the code. It does, when I ask. What I do is find where the thing breaks, and that instinct works the same whether a person wrote it or a machine did.

It works better now, if anything. Machines get it wrong much faster, and much more plausibly.

These days

I set it going at night and go to bed. In the morning sixteen of them have finished.

I used to do all of this myself, by hand. It was hard on the wrist.

What’s here

Four things.

• Built — eight tools I made and run. No demos. If it doesn’t run, I write down that it doesn’t.
• Teardowns — repos, articles and videos taken apart and judged. About one in three ends in “I didn’t take anything.”
• Writing — the notes that outgrew a commit message.
• Just out — a stockpile the machine fills daily and takes apart once. It is the only section I don’t write — what I pick out of it becomes a teardown.

What isn’t here

Work. The QA automation I’ve built for a living is several times this list, but the subject belongs to my employer, not to me. Where I’ve withheld something, I say so.

A list of wins. Headroom only ended after its conclusion had reversed twice, and in Prime Agent the best thing I took was something I had already written down five days earlier and forgotten. That’s what the work actually looks like.

Why write it down

Do QA long enough and you learn that a judgment you don’t record is a judgment you will make again. That happened to me badly enough once that I pulled every link out of two years of session logs and made the result searchable. The teardowns here come off that list.

That list is mine alone to read. This site is the outside of it — anything not left in a searchable form ends up known only to me.

Getting in touch

Repos are behind the GitHub link, bottom left. If you’re actually going to use any of this, an issue is the fastest way to ask.