YCW25· AI· DevtoolsTrainLoop
Reasoning Fine-Tuning
ActiveChecked 17h ago
Founders
- Jackson StokesFounder/CEO
- Mason PierceFounder/CTO
Same space
Competitors
Closest in what they build, same category.
CueBenchS26RL post-training for science reasoning and performance engineeringShared: reinforcement learningActive
Unsloth AIS24Open-Source Reinforcement Learning (RL) & Fine-tuning for LLMs.Shared: developer toolsActive
OsmosisW25Reinforcement Learning (RL) for AI AgentsShared: reinforcement learningActive
CartpoleX25Building reinforcement learning environmentsShared: reinforcement learningActive
Airtrain AIS22No-code data curation for LLM fine-tuning and evaluation.Shared: developer toolsInactive
Adjacent
Overlapping tags, a different niche.
Vibrant LabsW24Autonomously scaling environmentsShared: developer tools, reinforcement learningActive
hiloopS26Autoresearch as a service: we solve your hardest measurable problemsShared: developer tools, reinforcement learningActive
ThetaX25Specialized AI for Every JobShared: reinforcement learningActive
RiftenS26Earned intelligence for every companyShared: developer tools, reinforcement learningActive
UnifyW23Models that keep learningShared: reinforcement learningActive
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Batchmates in Winter 2025.
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CodevisorW25The fastest native app for agentic engineering.Active
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Outside YC
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About TrainLoop
TrainLoop makes it effortless for developers to supercharge LLM performance through reinforcement learning.
San Francisco, CA, USA
TrainLoop: questions
Which YC batch was TrainLoop in?
TrainLoop was in Y Combinator's Winter 2025 batch (W25).
Is TrainLoop still active?
Y Combinator lists TrainLoop as active.
Who founded TrainLoop?
TrainLoop's founders, as listed on its YC page: Jackson Stokes (Founder/CEO), Mason Pierce (Founder/CTO).
Where is TrainLoop based?
TrainLoop lists San Francisco, CA, USA as its location on YC's directory.
Not affiliated with Y Combinator. From YC's public directory. Logos via logo.dev; trademarks belong to their owners.