Building the universal integration layer for modern products and raising a Series A from GV with Romain Sestier & Guillaume Lebedel, Co-Founders @ StackOne

In this episode of Riding Unicorns, we're joined by Romain Sestier and Guillaume Lebedel, the co-founders of StackOne, a rapidly growing startup that’s building the universal integration layer for modern SaaS and AI products. Hot off the back of their $20M Series A led by GV, the duo joins us to share their journey, insights, and lessons from the trenches.

Romain and Guillaume have known each other for over a decade, having worked together across multiple companies before launching StackOne. Their deep co-founder chemistry and clarity of vision have helped them move fast and build credibility with customers and investors alike.

We dive into:

🔧 What StackOne does and why integrations are mission-critical infrastructure
 🧠 How they approached finding a co-founder (and why that came before the idea)
 🚀 Their path from idea to Series A, including early customer acquisition and GTM learnings
 💼 Building a high-talent, low-ego team and making tough hiring decisions
 💡 How to scale enterprise sales as a founder
 🔥 The mindset shift required to build a venture-scale company
 🧪 How they stay nimble while evolving the product and org structure
 📣 Tips on empowering internal champions and structuring a sales process that scales

This is a must-listen for any B2B SaaS or infrastructure founder looking to build something big, fast, and globally relevant.