Epsilab
Epsilab is a YC Fall 2026 (F26) company. Based in San Francisco, CA, USA. Team of 4.
About Epsilab
Summary
Epsilab builds reinforcement learning environments derived from real-world data, used to train AI agents on long-horizon, multi-step tasks. It targets applied AI research teams and frontier model developers who need realistic simulation grounds that go beyond synthetic or narrow benchmarks. The product replaces hand-crafted, toy RL environments with simulations grounded in actual workflows and multi-agent dynamics.
Go-to-market
Epsilab sells to AI research labs and model development teams building agentic systems, positioning its environments as infrastructure for RL training pipelines.
From the Y Combinator listing
Long horizon RL environments from real-life data
Applied AI research lab focused on RL for frontier model training. Our research and evals cover real-world environment simulation, long-horizon workflows, and multi-player agents, etc.
Facts
- B2B / B2B
- San Francisco, CA, USA
- 4
- Active
- Early
Founders (4)
- Fengjiao Peng
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