Fundraising Fox

William Barthell

Founder

Co-Founder & CTO at Janet AI

San Francisco, California, United States

FoundedJanet AI · YC

About

William Barthell is co-founder and CTO at Janet AI. Previously, he was the first engineer at a cryptocurrency startup where he worked on automated market maker design for Solana token trading, and holds a bachelor's degree in computer science from UW-Madison.

Co-Founder & CTO at Janet AIYC S25

Intro paths

YC

William went through Y Combinator (Summer 2025) — any YC alum in your network can reach them through the YC community.

GP

Their group partner at YC was Tyler Bosmeny, General Partner at Y Combinator — the partner who ran Janet AI's batch and knows the company first-hand. YC profile ↗

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In turn, William can intro founders to Janet AI's investors below.

Janet AI's investors · 1

Y CombinatorSan Francisco · $500K checks · since 2025

Co-founders at Janet AI

ASAdhit Sankaran
Adhit SankaranCo-Founder & CEO

Experience

  1. Janet AI (YC S25)Co-Founder & CTOcurrent2025 — presentSan Francisco, California, United States
  2. Stealth StartupFounding Engineer2024New York, New York, United States

Frequently asked questions

Who is William Barthell?
William Barthell is co-founder and CTO at Janet AI. Previously, he was the first engineer at a cryptocurrency startup where he worked on automated market maker design for Solana token trading, and holds a bachelor's degree in computer science from UW-Madison.
Where does William Barthell work?
William Barthell is Co-Founder & CTO of Janet AI.
What companies did William Barthell found?
William Barthell founded Janet AI.
Where did William Barthell go to school?
William Barthell studied at Y Combinator (S25); University of Wisconsin-Madison (Bachelor's degree, Computer Science); Saratoga High School.

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University of Wisconsin-Madison mafia59

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Shared employers

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Adhit SankaranCo-Founder & CEO at Janet AI

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