Nubank

Nubank built its own stack from the ground up. The fintech, publicly traded on the NYSE (NU), runs a digital financial services platform serving 127 million customers across Brazil, Mexico, and Colombia. Proprietary technology and data-driven decision-making aren't buzzwords here - they're the architecture. When you're the primary interface for that many people's money, the threat surface is everything: fraud at scale, credential stuffing on accounts that actually hold value, API abuse against a platform designed to be open and fast. The company's mission to fight financial complexity means every security control has to work without becoming the friction it was built to eliminate. The security challenge is shaped by scale and geography. Operating across three Latin American markets means navigating distinct regulatory regimes, payment ecosystems, and fraud patterns simultaneously. The team works on a technology stack the company owns end-to-end - no inherited legacy layers to blame, but also no vendor to offload responsibility to. That means security engineering is embedded in product development, not bolted on after deployment. Domains likely span application security for mobile-first products, cloud infrastructure hardening, fraud detection systems, and identity verification - all built on top of the proprietary platform Nubank maintains itself. For a cybersecurity team, the draw is the combination of high-impact scope and genuine engineering ownership. The company's public listing brings SEC and NYSE compliance obligations layered on top of financial regulatory requirements in multiple countries. Culture signals around transparency and responsible lending translate into an environment where security isn't an afterthought - it's a prerequisite for the trust model that keeps 127 million customers from walking. The work is concrete: defending real financial infrastructure at regional scale, with the tooling and access that come from building it yourself.