Armin Ronacher, who wrote Flask and Jinja, ran the purest vibe coding experiment I have seen: one prompt to GPT-6 Astra, no human review, and 35 hours of the agent working alone. His write-up, "Astra for Coding: Why Are We Doing This Again?" , reports about $1,200 in API cost, a net 75,000 lines of code and "absolutely nothing of value". If you let an agent run while you sleep, the traces he pulled out are a preview of your repo. TL;DR One prompt, 35 hours, about 1 b...