(I made this port) Fwiw I personally had no reason to do this port beyond using it as a benchmark of the agentic capability of Fable, where something of this shape is IMO a way better gauge than those dumb X.com 'I oneshot game with models X/Y/Z this is how it compares'
I published the actual prompts, and you can see quite clearly that vs Opus which is ok at implementing one big feature, Fable was really able to push through a good chunk of the port. That said it definitely didn't one-shot the port, it also didn't figure out a broken docker sbx sandbox by itself, and also later needed some gaslighting into thinking that the port is not really that hard (by any human measure it was quite hard given the scope of code involved.. The nearly 200MB wasm binary is mostly code afaict..). So there are some clear patterns of how the model was trained and also roughly the scope of task visible in those traces. What I see is that it likes prompts that would take an L4/L5 2-4 weeks to do with Cursor ~2 years ago, more needs some direction and deliberate prompting.