Part 6 of the AI Agents series. The full build story of the browser-playable Snakes & Ladders arena that the six-role software company from Part 5 delivered — beginning, as these things do, with the two times it failed first.
This is a field report on agentic development: what actually happens when you hand a real software project to autonomous AI coding agents and let them run a full development lifecycle. Most guides to agentic coding describe the theory — the roles, the loops, the guardrails. This one is the evidence: three attempts, two abandoned toolchains, a hallucinated graphics API, an AI-issued quality certificate that certified a layer it had never tested, twenty-eight defects closed without being repaired, and a finished game you can play in your browser right now. If you want to know whether AI agents can build software — and, more usefully, how you would ever know — that is what this post is about.
What this post covers:
- Why this game was built three times — twice as native C, by two different agentic drivers, and both times it died.
- What a hallucinated API actually looks like when the compiler grades it, including the subtler case of a function that was real once and has since been removed.
- A QA certificate declaring the application 100% defect-free whose own footnote admits it never tested the layer containing the only visible bug.
- The stretch where my own instruments were wrong four times in a row and the person watching the screen was right every time.
- Twenty-eight defects found by an independent reviewer, closed without being repaired, and then actually repaired.
- Why a finished, tagged, CI-green project needed a week and a full rollback to survive meeting one phone.
- The finished game running on 19 GitHub-hosted runners across three operating systems and two CPU architectures.
The finished arena, playing itself. Procedural board, SVG snakes and ladders, four autonomous players, twelve audio cues — and no build step anywhere in sight.
In Part 5 I forked a production coding CLI into a six-role software development company — CEO, CPO, CTO, programmer, reviewer and tester, running as native subagents on free NVIDIA NIM models. That post was about the harness. It closed by naming the thing the harness actually produced and promising the details here: a four-player Indian Snakes & Ladders arena that plays itself in any browser, with no build step and no server.
This is that story. It does not begin where you would expect, because the browser was not the plan. It was the third plan.