Chemical engineer ships 9K-line game via LLMs alone

The real story isn't the game — it's the hard-won workflow insights from a non-developer who pushed LLMs past their comfort zone on a large, stateful codebase.

• –The "patch file" LLM strategy (force exact find/replace blocks, never full rewrites) is the key takeaway — a practical fix for truncation and hallucination that every vibe-coder will eventually rediscover the hard way
• –Per-frame elliptical boundary math to confine Matter.js rigid bodies inside CSS circles shows the depth LLMs can enable, not just shortcut — this isn't a toy project
• –Vanilla JS without React exposed the unsexy discipline problem: strict teardown of setInterval loops and physics bodies on every map transition — exactly what frameworks handle silently
• –HN reaction was unusually unanimously positive; commenters specifically praised the LLM workflow transparency over the game itself, signaling strong appetite for honest non-dev build diaries
• –Favorably compared to SimRefinery, the 1990s Maxis classic — a niche but meaningful benchmark for educational simulation depth