Sebastian Crossa

Sebastian Crossa is the Co-Founder of ZeroEval, an early-stage B2B software startup, and is currently based in New York City. At the two-person company, which was selected for the Y Combinator Summer 2025 cohort, he helps drive growth, improve internal processes, scale operations, and shape overall business strategy. Previously, he served as a founding engineer at Micro, an email technology startup backed by the venture capital firm Andreessen Horowitz, and worked at Atrato Pago, a Y Combinator Winter 2021 alumni company. Born and raised in Mexico, his early entrepreneurial experience includes building and scaling Minecraft servers during high school, and since 2025, he has maintained LLM Stats, a project tracking large language model metrics. Today, Crossa focuses his career on full-stack web engineering and early-stage technology startup execution within the B2B and artificial intelligence software sectors.