Staff Security Engineer [AppSec]

Responsibilities

• Define and implement application security strategies, including LLM and GenAI components
• Collaborate with development teams to integrate security from the start of the SDLC
• Perform architecture, code and design reviews to identify vulnerabilities
• Define guardrails for LLM applications, addressing prompt injection and excessive agency
• Establish guidelines for secure use of AI-assisted development tools
• Provide technical guidance and security training to development teams
• Apply SAST, DAST, SCA and secret scanning in CI/CD pipelines
• Participate in security incident analysis and response

Requirements

• Higher education (completed or in progress) in Information Security, Computer Science, Information Systems or Software Engineering
• Knowledge of common attack vectors and threat modeling
• Experience with API and mobile application protection
• Knowledge of cloud security services (AWS, Azure or GCP)
• Familiarity with agile multidisciplinary teams
• Familiarity with LLM application risks (OWASP Top 10 for LLM Applications, MITRE ATLAS)
• Ability to communicate concisely and assertively; English reading and communication

Preferred Qualifications

• Experience in incident root cause analysis
• Experience with financial regulatory requirements (Bacen, PCI, SOX)
• Strong programming skills
• Experience threat modeling LLM systems in production (chatbots, copilots, agents, RAG)
• Experience with NIST AI RMF or ISO/IEC 42001

Benefits

• Fixed salary and variable compensation package
• Health and dental insurance with co-payment
• 24/7 telemedicine service
• Meal and food allowances
• Childcare allowance
• Life insurance
• Fuel or commuting allowance
• Home office allowance for hybrid or remote contracts
• Educational development platform

About the Company

Stone is Brazil's largest independent payments company, with over fifteen thousand employees across the country. It is a technology and financial services company focused on the customer.