Auto-Refactoring 100k Lines of Code in 47 Hours
jxnlco · x · 2026-07-11
A developer shared that they let GPT-5.6-Sol run continuously for 47 hours with almost no intervention, successfully refactoring a bloated local app.
Key points:
- The original app had about 105,704 lines of code and was a "slop-coded" personal work tool.
- The goal was to rewrite it with a new architecture, reducing code volume by 70% and testing time by 75%.
- Previous attempts to auto-rebuild with other models failed, but this attempt succeeded, resulting in a faster app with fewer bugs.
The highlight of the post is demonstrating the viability of long-running, autonomous coding agents for real-world refactoring tasks.
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