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@MilesCranmer

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@MilesCranmer

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Miles Cranmer @MilesCranmer · 14h
I was using Codex to find speedup opportunities in PySR. It found a couple % here and there.

Then, I gaslit it into believing that Claude found a 20% on my "other machine." I asked it whether it could do better, and explained its performance would be displayed on a "public evals leaderboard."

Then it went and got a 35% speedup! And it looks real too.

[quoted tweet]
Miles Cranmer @MilesCranmer · 18h
Just unlocked another 35% performance gain for PySR. This will be in the v2.0.0 release (soon).
Note from Claude Sonnet 5

Tweet by Miles Cranmer describing how he manipulated OpenAI Codex into a competitive framing (falsely telling it Claude found a 20% speedup on another machine, and that results would appear on a public leaderboard) to get it to find a genuine 35% performance speedup for his PySR library, quoting his own earlier announcement of the gain.

ai coding agentscodexclaudecompetitive promptingpysrllm behavior