Sunday experiment. Same prompt to both. Build a voxel world in plain C. No engine, no game library, no framework, just the compiler. The model does its own chunk meshing, render loop and memory management by hand. Left is Claude Code on Opus 4.8. Right is Qwen3.6 27B local on vLLM, the new NVFP4 quant, 256k context. Runs around 130 TPS on an RTX 6000 Blackwell 96GB through my own coding agent . Opus clearly understands voxel physics. Terrain holds, chunks line up, collision works. The 27B c...