A reader named Ryan left the sharpest comment on my last post. The gist: it was jargon-heavy, kept restating "you have to test the AI's output" in new words, and read more like a pitch deck than a case study. He was right, and he pointed at the fix himself: walk through one real task. What changed, what caught the problem, what proof was required, where did a human step in.
So here is one task, start to finish. Everything below is public and runnable. No withheld details, no diagrams of boxes with arrows.
The setup, in two sentences
My match-3 game runs on a plain-Java rules engine. It runs two ways: on a JVM (where the tests and CI live) and in the browser, compiled to JavaScript by TeaVM, so the same Java drives a real playable board.
That second runtime is not just a demo. Running one piece of logic on two different machines gives me a free check: where the two disagree, one of them is wrong. I did not have to write down the right answer. I just had to notice a disagreement.
