Security Engineer

Meta's Security Engineering team is seeking a Security Engineer to help protect billions of users and Meta's global infrastructure from evolving threats. In this role, you will conduct security assessments, vulnerability research, and threat modeling across Meta's products and systems — spanning mobile applications, web platforms, backend services, and internal infrastructure. You will identify systemic security gaps, drive mitigations at scale, and partner with engineering teams to embed security best practices into the software development lifecycle. Your work will directly reduce risk for Meta and its users by turning one-off security findings into durable, scalable defenses.Responsibilities

Conduct security assessments, penetration testing, and vulnerability research across Meta's web, mobile, and backend systems to identify and remediate security risks

Perform threat modeling and security architecture reviews for new and existing products and infrastructure

Identify systemic security gaps and drive cross-functional mitigations that scale beyond individual findings

Develop and improve security tooling, automation, and detection capabilities to enhance the team's ability to identify and respond to threats

Collaborate with product and infrastructure engineering teams to define security requirements and integrate security controls into the software development lifecycle

Lead complex security investigations and incident response efforts, coordinating with cross-functional partners to resolve issues and prevent recurrence

Translate security findings into actionable, prioritized recommendations for engineering and leadership audiences through clear written documentation

Mentor other engineers on security best practices, contribute to team culture, and support recruiting and onboarding efforts

Manage oncall security responsibilities independently, triaging and resolving security issues with cross-functional support as needed

Identify and land new security initiatives on the team roadmap that address high-complexity, ambiguous risk areas aligned with broader team strategy

Minimum Qualifications

6+ years of experience in security engineering, including hands-on work in penetration testing, vulnerability research, or security assessments of web, mobile, or backend systems

Experience performing threat modeling and security architecture reviews for large-scale software systems

Experience identifying systemic security risks and driving cross-functional remediation efforts that result in scalable, durable improvements

Experience developing or improving security tooling, automation, or detection capabilities to support team-level security operations

Experience communicating security findings and risk assessments in writing to both technical and non-technical stakeholders

Preferred Qualifications

Experience with security automation, static or dynamic analysis tooling, or building internal security platforms

Demonstrated ability to integrate AI tools to optimize/redesign workflows and drive measurable impact (e.g., efficiency gains, quality improvements)

Familiarity with security considerations specific to large-scale distributed systems, mobile platforms (iOS or Android), or cloud infrastructure

Experience with offensive security techniques including exploit development, binary analysis, or red team operations

Demonstrated ongoing AI skill development (e.g., prompt/context engineering, agent orchestration) and staying current with emerging AI technologies

Proficiency in one or more programming or scripting languages (e.g., Python, C/C++, Java) used to develop security tools or analyze vulnerabilities

Experience adhering to and implementing responsible, ethical AI practices (e.g., risk assessment, bias mitigation, quality and accuracy reviews)