Janus
Janus is a YC Spring 2025 (P25) company. Based in San Francisco, CA, USA. Team of 2.
About Janus
Summary
Janus builds simulation-based evaluation infrastructure for AI agents. It runs agents through high-fidelity simulated environments to surface failures in reasoning, compliance, tool use, and performance before deployment. The resulting datasets serve as benchmarks and feed post-training pipelines, replacing manual or ad-hoc evaluation workflows.
Go-to-market
Janus targets engineering and product teams building and shipping AI agents, reached through developer-facing channels and a demo booking flow on its site.
From the Y Combinator listing
Evaluate AI Agents with Simulation Environments
Janus automates AI evaluations by using high-fidelity simulation environments, catching failures in reasoning, compliance, tool usage, and performance. The resulting datasets benchmark products and feed post-training loops to continuously improve performance over time.
Facts
- B2B / B2B -> Infrastructure
- San Francisco, CA, USA
- 2
- Active
- Early
Founders (1)
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