12 hours, 4,518 lines of tooling it built for itself, and the app still loads in 35 seconds (GPT-6.1 Sol case report)

A solo developer used Codex CLI 0.159.3 with gpt-6.1-sol for over 12 hours to optimize an internal reporting app that took 35 seconds to load. The AI generated 4,518 lines of tooling but failed to implement a fix or improve load times. The developer reported no integrated fix, no measured improvement, and significant added complexity, leading to the cancellation of their $200/month subscription due to the lack of sustained value.

This report details a specific failure case of GPT-6.1 Sol, unlike many success stories, highlighting its inability to improve app load times despite generating 4,518 lines of code.