Osmosis

Forward-deployed reinforcement learning for AI agents

Osmosis (YC W25) is a post-training platform that fine-tunes models with reinforcement learning so companies' agents beat foundation models on specific tasks in performance, cost, and latency. Founded by Kasey Zhang and ex-TikTok tech lead Andy Lyu.

Angel investors include Paul Graham and Guillermo Rauch

Websiteosmosis.ai
DomainsMachine Learning
LocationSan Francisco
Team size1-10
Founded2024
FundingSeed, $7M (CRV, Audacious Ventures, YC)
FoundersKasey Zhang, Andy Lyu

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