Claude Opus 4.6 vs. GPT-5.3 Codex: How I shipped 93,000 lines of code in 5 days
Lenny's Newsletter | Substack [Unofficial]
February 11, 2026
I tested GPT-5.3 Codex vs. Claude Opus 4.6 on real code, shipping 44 PRs in five days to see which AI model actually works best
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