# David Winer

> David Winer is the Co-Founder and CTO of Ciro (YC S22), an AI-powered go-to-market platform that automates sales prospecting from target identification to booked meetings. With roots in applied mathematics, a Berkeley EECS master's, and a Stanford MBA, he spent time at Bain, Pure Storage, and Google (where he served as PM for the Kotlin programming language and sat on the Kotlin Foundation board) before co-founding Ciro in 2022 with Brown University friends Richard Lee and Ross Geiger. Ciro raised $3.8M in seed funding from CRV, Y Combinator, and SV Angel, and runs on a stack anchored by Anthropic Claude, OpenAI, and Elasticsearch. Outside the office, David self-identifies as an 'exceedingly obscure internet personality' and writes a personal blog mixing statistical deep-dives with essays on bike theft and vegetarianism.

- **Role:** Co-Founder & CTO at Ciro
- **Organizations:** Ciro, Y Combinator, Google, Pure Storage, Bain & Company, Kotlin Foundation
- **Nationality:** American
- **Education:** Bachelor's in Applied Mathematics, Brown University, Master's in Electrical Engineering & Computer Science, UC Berkeley, MBA, Stanford University
- **Known for:** Co-founded Ciro (YC S22), raising $3.93M total funding, Served as Product Manager for Kotlin programming language at Google, Secretary of the Kotlin Foundation Board

## Career timeline

- **Early career** — Management Consultant at Bain & Company
- **Mid career** — Software Engineer at Pure Storage, working on ML and data science
- **Pre-Ciro** — Co-founded Wage, a startup that raised $5M in funding
- **Pre-Ciro** — Product Manager for the Kotlin Programming Language at Google; Secretary of the Kotlin Foundation Board
- **2022** — Co-founded Ciro with Richard Lee and Ross Geiger; accepted to Y Combinator S22 batch
- **2022-10** — Ciro raised $3.8M seed round led by CRV, with Y Combinator and SV Angel
- **2025-05** — Ciro launched on Product Hunt, reaching #2 Product of the Day with 633 upvotes

## Achievements

- Co-founded Ciro (YC S22), raising $3.93M total funding
- Served as Product Manager for Kotlin programming language at Google
- Secretary of the Kotlin Foundation Board
- Previously co-founded Wage, which raised $5M in funding
- Built AI prospecting platform scanning 500M+ profiles with verified contact data from 15+ sources
- Ciro reached #2 Product of the Day on Product Hunt with 633 upvotes (May 2025)

## Latest updates

- **2025-05** — Ciro launched on Product Hunt, achieving #2 Product of the Day with 633 upvotes
- **2022-10** — Ciro raised $3.8M seed round from CRV, Y Combinator, and SV Angel

## Links

- Website: https://www.davidjwiner.com/
- LinkedIn: https://www.linkedin.com/in/david-winer/
- Twitter/X: https://x.com/davidjwiner
- GitHub: https://github.com/davidjwiner
- Instagram: https://www.instagram.com/davidjwiner/

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Profile page: https://yespress.io/david-winer
Published by YesPress — https://yespress.io
Last updated: 2026-05-06