Sanctum
Sanctum is a YC Fall 2025 (F25) company. Based in San Francisco, CA, USA. Team of 2.
About Sanctum
Summary
Sanctum builds an AI-powered user simulation platform for software teams shipping new features. It ingests real session recordings to construct behavioral user models, then runs those models against code changes to catch bugs, UX regressions, and performance problems before release. The product replaces manual QA scripting and end-to-end test authoring by generating and executing realistic user flows automatically.
Go-to-market
Engineering and product teams at software companies are the buyers; the platform connects to existing CI pipelines and observability tooling, positioning adoption as a drop-in addition to a team's current release workflow.
From the Y Combinator listing
Catch software issues with user simulations
Sanctum lets you launch new features to agents that mimic your real users. We build AI user models from your session recordings and run them against your changes to surface bugs, UX issues, and performance problems early.
Facts
- B2B / B2B
- San Francisco, CA, USA
- 2
- Active
- Early
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