Kasey Zhang

Kasey Zhang co-founded and ran a gaming startup for two years before it was acquired, then worked at venture firms focused on AI and data before returning to building, according to Osmosis's YC page. He is now co-founder and CEO of Osmosis, which applies reinforcement learning to AI agents.

Partnering With Andy Lyu

Zhang and co-founder Andy Lyu have known each other for more than a decade. Lyu worked on data architecture for TikTok recommendations as the company's 5th and youngest US hire, and later became a tech lead running data infrastructure for recommendations.

Learning Loops at Osmosis

Foundation models are "frozen snapshots of intelligence," investor Ashley Smith wrote in a Vermilion Cliffs note on the seed. Once deployed, a model can make the same mistake thousands of times and never notice. Osmosis aims to let deployed systems observe outcomes, learn from reward signals and adapt.

Osmosis's Seed Investors

Osmosis raised a $6.3 million seed round led by Audacious and CRV. When Smith first met Zhang and Lyu, "they weren't pitching hype," she wrote. "They were deep in the weeds of reinforcement learning infrastructure." Angel investors include Paul Graham and Guillermo Rauch.