Thomas Césaré-Herriau

Thomas is Co-Founder and CTO at SpotPay, a Y Combinator-backed global borderless neobank that enables cross-border payments on stablecoins. He was engineer #4 at Brex, where he became Principal Software Engineer and built critical infrastructure including the observability platform for Elixir microservices.
Thomas studied Computer and Information Sciences at Ecole Centrale Paris (CentraleSupelec), graduating in 2013. Prior to Brex, he worked as a software engineer at Google.
Thomas joined Brex when it was just a dozen people working from a mezzanine office in San Francisco and helped scale the company's engineering organization. He managed 3 teams at Brex, worked across 4 different offices, and relocated to NYC to start the Observability team.
SpotPay was founded in 2025 and joined Y Combinator's Winter 2026 batch, raising $450K. The company is based in San Francisco and provides users one account for receiving money from abroad, paying locally, spending with the SpotPay card, and earning on their balance.
Thomas brings deep technical expertise in distributed systems, event-driven architecture, and financial infrastructure from his time building core systems at two major fintech unicorns. He has authored technical articles and spoken at conferences about observability and microservices architecture.