Sr./Staff Security Engineer

This position is posted by Jobgether on behalf of a partner company. We are currently looking for a Sr./Staff Security Engineer in Brazil.

In this high-impact role, you will be the first dedicated security engineering hire, shaping the foundation of product security across a fast-scaling AI risk decisioning platform. You will operate at the intersection of product, infrastructure, and AI/LLM security, defining how security is embedded into every layer of the system. This is a hands-on, strategic position where you will influence architecture, engineering practices, and company-wide security culture. You will work closely with product and engineering teams to design secure-by-default systems for fintech and enterprise customers. The environment is highly technical, fast-moving, and mission-driven, with strong ownership expectations. Your work will directly contribute to safer digital transactions and more resilient financial systems.

• Own end-to-end threat modeling across APIs, event ingestion systems, and AI-driven products, ensuring secure multi-tenant architecture and safe data handling.
• Design and implement authentication, authorization, and role-based access control systems across platforms, including scalable identity and access strategies.
• Build and lead the application security program from the ground up, including SAST, SCA, secret scanning, IaC scanning, and container security in cloud-native environments.
• Define and enforce security guardrails for LLM and agent-based systems, including prompt injection defenses, output validation, and abuse monitoring.
• Lead incident response processes, vulnerability management, and responsible disclosure workflows.
• Establish secure-by-default engineering practices, including documentation such as SECURITY.md and a centralized threat registry.
• Partner with IT and engineering teams on audits, access reviews, and security evidence collection.

Requirements:

• 5+ years of software engineering experience, with at least 3+ years focused on application or product security in fintech or data-intensive environments.
• Strong hands-on experience in Java and/or Python with the ability to review and secure production-grade code.
• Deep understanding of authentication and authorization standards such as SSO, SAML, OAuth 2.0, JWT, mTLS, and JOSE.
• Experience with multi-tenant architectures, PII handling, and data protection strategies.
• Solid knowledge of AWS security services such as IAM, KMS, Secrets Manager, and VPC, as well as Kubernetes environments.
• Experience collaborating with engineering teams to integrate security early in the development lifecycle.
• Strong communication skills and ability to influence technical decisions across teams.

Benefits:

• Competitive salary under a CLT employment model.
• Stock options in the company.
• Full coverage of medical and dental insurance for employees and dependents.
• Life insurance and long-term disability coverage fully covered.
• Monthly meal allowance via Caju Card.
• Remote-first and flexible working culture.
• Family-friendly environment with regular team events and offsites.
• Strong focus on learning, growth, and professional development.
• Opportunity to directly impact the security of global digital financial systems.