Cartpole (YC X25) — Building reinforcement learning environments
We're creating reinforcement learning environments for training frontier models.
Cartpole is a Y Combinator company in the Spring 2025 batch. Its directory entry describes it as: Building reinforcement learning environments. The founder listed is Mateo Perez (Founder/CEO) (Y Combinator directory entry, April 14, 2025).
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Mateo Perez
Founder/CEO
Building Cartpole. PhD @ CU Boulder.
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Example from a real report (our sample on Target): “The Q2 2026 earnings report, published August 19, 2026, showed adjusted EPS of $2.46 against an expected $2.33” Source: CNBC
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What They Do, And How The Money Works
Who Runs It, And How To Reach Them
The Money: Funding, Valuation, Runway
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Warning Bells
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