# Polymorph

> Polymorph is a San Francisco startup (Y Combinator W26) building personalization infrastructure for consumer and self-serve software teams. It turns product behavior into live user profiles and uses AI agents to run thousands of continuous experiments, automatically tailoring the timing, channel, and content of lifecycle messaging - push, in-app, email, SMS - for each user, with clear attribution on what drove conversion. The pitch: give any team the kind of adaptive, per-user experience that companies like Meta, TikTok, and Google spend years and whole orgs building.

- **Founded:** 2026
- **Headquarters:** San Francisco, California, United States
- **Founders:** Andrew Sy (Co-founder & CEO), David Nie (Co-founder), Manas Purohit (Co-founder)
- **Team size:** 3-4
- **Products:** Polymorph Personalization Infrastructure, Experimentation Agents
- **Notable:** Accepted into Y Combinator's Winter 2026 batch., Supports 3.5M+ users across customers., Drove a 3.6x lift in dormant-user reactivation for an early customer.

## Products & services

- **Polymorph Personalization Infrastructure** — Turns product behavior into live user profiles and automatically personalizes the timing, channel, and content of lifecycle messaging (push, in-app, email, SMS) for each user, with attribution on what drove conversion.
- **Experimentation Agents** — AI agents that continuously run thousands of experiments across product surfaces and lifecycle engagement, distributing the craft of product direction across automated systems.

## Achievements

- Accepted into Y Combinator's Winter 2026 batch.
- Supports 3.5M+ users across customers.
- Drove a 3.6x lift in dormant-user reactivation for an early customer.

## Latest updates

- **2026-01** — Polymorph joins Y Combinator's Winter 2026 batch and closes an initial $130K on a seed.
- **2026-01** — YC highlights Polymorph helping consumer and self-serve teams deliver personalized lifecycle messaging, citing a 3.6x reactivation lift for an early customer.

## Links

- Website: https://usepolymorph.com
- LinkedIn: https://www.linkedin.com/company/usepolymorph

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Profile page: https://yespress.io/polymorph-yc-w26
Published by YesPress — https://yespress.io
Last updated: 2026-07-30