TrainLoop
TrainLoop is a YC Winter 2025 (W25) company. Based in San Francisco, CA, USA. Team of 6.
About TrainLoop
Summary
TrainLoop builds specialized post-training models for enterprises in pharma, biotech, logistics, and banking, focusing on long-horizon tasks that require deep domain expertise. Working alongside human experts, TrainLoop distills their judgment into proprietary models through reinforcement learning and post-training research. This replaces the effort of fine-tuning general-purpose LLMs in-house or relying on off-the-shelf models that underperform on complex, domain-specific workflows.
Go-to-market
Enterprise teams in regulated and technical industries are the buyers, brought in through a structured partnership process that runs from objective definition through model training to production deployment.
From the Y Combinator listing
Reasoning Fine-Tuning
TrainLoop makes it effortless for developers to supercharge LLM performance through reinforcement learning.
Facts
- B2B / B2B -> Engineering, Product and Design
- San Francisco, CA, USA
- 6
- Active
- Early
Founders (1)
- Jackson Stokes
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