Lead Security Engineer (AI) – Product Security

About Nubank

Nu is one of the largest digital financial platforms in the world with more than 127 million customers across Brazil Mexico and Colombia. Guided by our mission to fight complexity and empower people we are redefining financial services in Latin America and this is still just the beginning of the purple future were building.

Listed on the New York Stock Exchange (NYSE: NU) we combine proprietary technology data intelligence and an efficient operating model to deliver financial products that are simple accessible and human.

Our impact has been recognized by global rankings such as Time 100 Companies Fast Companys Most Innovative Companies and Forbes Worlds Best Bank. Visit our institutional page the role

AI is core to how Nubank builds products and securing it is one of the most critical and forward-looking challenges in the company. The AI Security team part of Nubanks Information Technology & Security area is responsible for ensuring that AI systems are developed and operated safely and securely at scale across LLM-powered applications autonomous agents and the infrastructure that supports them.

As Lead Security Engineer (AI) you will own and drive Nubanks defensive security strategy for AI products and internal tools. You will define frameworks set technical direction build runtime protections and enable engineering teams across the company to ship AI systems securely by default. This role sits at the intersection of cutting-edge AI and high-stakes security and your work will directly shape how one of the worlds largest fintechs builds trustworthy AI at scale.

Youll be Responsible For

• Leading the security strategy for Nubanks AI systems covering LLM-powered applications AI agents and their underlying infrastructure and building the standards and frameworks that guide secure AI deployment across the company.
• Securing AI agents and autonomous workflows by hardening tool usage enforcing appropriate permission levels and monitoring agent behavior and decision-making in production.
• Designing and enabling secure architectural patterns for AI applications including LLM-based services and agent orchestration systems.
• Developing AI-specific detection and monitoring capabilities to identify abuse misuse and anomalous behavior including telemetry across prompts responses tool usage and agent execution.
• Designing and implementing runtime protections for LLM applications such as prompt injection detection jailbreak protection abuse detection and output safety controls.
• Collaborating with AI engineers and platform teams to integrate security controls into AI development and deployment pipelines.
• Staying current with emerging threats and AI security trends translating them into concrete controls guidelines and standards across Nubanks engineering organization.

We Are Looking for a Person Who Has

• Deep expertise in product security application security or cloud security combined with hands-on experience building AI agent systems.
• A proven track record leading cross-team technical initiatives setting standards and driving adoption without direct authority.
• Experience designing and implementing secure systems and controls in production environments.
• Hands-on experience with runtime security controls (input validation abuse detection policy enforcement) in high-throughput production systems.
• Solid familiarity with LLM application architectures including prompt pipelines tool use and RAG and their threat surfaces such as prompt injection data exfiltration and jailbreaks.
• Strong understanding of agentic systems and AI infrastructure with the ability to threat-model novel and non-deterministic systems.
• Experience building monitoring telemetry and alerting for production systems.
• Strong programming skills in at least one production language with the ability to read and review code across the AI stack.

Location

• Durham United States
• Miami United States
• Palo Alto United States
• Washington DC United States

Our Benefits

• Opportunity of earning equity at Nu
• Medical Insurance
• Dental and Vision Insurance
• Life Insurance and AD&D
• Extended maternity and paternity leaves
• Nucleo - Our learning platform of courses
• NuLanguage - Our language learning program
• NuCare - Our mental health and wellness assistance program
• 401K
• Saving Plans - Health Saving Account and Flexible Spending Account
• Work-from-home Allowance
• Relocation Assistance Package if applicable.

Work Model for this Role

Hybrid 23 times/week: Our hybrid work model brings us to the office at least twice a week on strategic days designed to maximize team connection and collaboration. For more details visit Experience:

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