# Romain Sestier

> Romain Sestier is the co-founder and CEO of StackOne, an integration platform that lets B2B SaaS products and AI agents connect to hundreds of enterprise systems through one unified API. After a decade spent maintaining integrations by hand at companies like Maxymiser, ContentSquare and Yieldify, and after building a product from zero to $1 billion in incremental revenue at Google, he and long-time collaborator Guillaume Lebedel started StackOne in 2023 to build the integration layer they always wished existed. The company reached six-figure revenue within weeks of launch and raised a $20M Series A led by GV in May 2025.

- **Role:** Co-founder & CEO at StackOne
- **Organizations:** StackOne
- **Nationality:** French
- **Education:** Business Management & Marketing, Royal Holloway, University of London
- **Known for:** Co-founded StackOne, reaching six-figure revenue within weeks of launch, Raised a $20M Series A led by GV in May 2025 (total funding ~$23.6M), Assembled a backer list spanning GV, Sequoia, GitHub, XTX Ventures, OpenAI, Microsoft and Workday Ventures

## Career timeline

- **2014** — Joined Maxymiser (later acquired by Oracle), where he met future co-founder Guillaume Lebedel who was building integrations
- **2016** — Head of UK Services at ContentSquare, opening the UK office and leading A/B testing tool integrations
- **2016** — Co-founded and led Upper.ai as CEO (through 2019), reaching around $100k revenue
- **2018** — VP of Product & Customer Success at Yieldify (acquired by Publicis), managing ~70 people and its SaaS integration strategy
- **2020** — Joined Google - co-founder and product lead at Area 120, Google's in-house incubator
- **2021** — Lead Product Manager for Ads Sales Intelligence at Google; helped build an AI insights product from $0 to $1B in incremental revenue
- **2023** — Co-founded StackOne with Guillaume Lebedel; raised $3.6M seed from Episode 1 Ventures
- **2025** — Raised $20M Series A led by GV (May 2025); StackOne reaches 450+ integrations and 27,000+ actions

## Achievements

- Co-founded StackOne, reaching six-figure revenue within weeks of launch
- Raised a $20M Series A led by GV in May 2025 (total funding ~$23.6M)
- Assembled a backer list spanning GV, Sequoia, GitHub, XTX Ventures, OpenAI, Microsoft and Workday Ventures
- Grew StackOne to 450+ agent integrations, 27,000+ production-ready actions and 10M+ API calls
- Achieved SOC2 Type II, HIPAA, GDPR and CCPA compliance
- At Google, helped scale a data insights product delivering $1B in incremental revenue
- As VP at Yieldify, led product and customer success for a global team of around 70

## Latest updates

- **2025-05** — StackOne raised a $20M Series A led by GV
- **2025** — Repositioned StackOne as the integration infrastructure for AI agents, surpassing 450+ integrations and 27,000+ actions

## Links

- Website: https://stackone.com
- LinkedIn: http://www.linkedin.com/in/romainsestier

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Profile page: https://yespress.io/romain-sestier
Published by YesPress — https://yespress.io
Last updated: 2026-07-29