Fullstack Staff Engineer

About DEUNA 🧡   DEUNA is a rapidly growing startup revolutionizing global commerce with ATHIA, our AI-powered orchestration and payments platform that helps large enterprises boost approval rates, reduce costs, and unlock new revenue. Built by the team behind DEUNA—the fastest-growing Commerce OS in Latin America—ATHIA combines payment intelligence, checkout optimization, and data orchestration in one powerful solution.   With deep integrations across 300+ PSPs and alternative payment methods, and over 20% of Mexico’s digital economy running through our platform, we simplify global payments through a single integration and centralized reconciliation. We are a rapidly growing startup expanding into the U.S. to meet the urgent needs of large retailers, marketplaces, airlines, and QSRs. Join us to shape the future of payments! 🚀   Visit https://www.deuna.com/ to learn more about us! Role Overview We are looking for a Staff Software Engineer – Fullstack to act as a senior technical leader across our engineering organization. This is a high-impact individual contributor role, focused on driving architecture, setting technical direction, and solving complex, cross-team challenges. You will partner closely with Engineering, Product, and leadership to ensure our systems scale reliably as the business grows. This role is not focused on people management — instead, you will operate as a technical authority and multiplier, influencing multiple teams and raising the overall engineering