Security Engineer: Build Scalable Defenses for Global Apps

Meta; City of Westminster; On-site; GBP 90,000 - 120,000; Full time

Job summary

Meta is seeking a Security Engineer to protect billions of users and Meta's global infrastructure. You will perform security assessments, threat modeling, and vulnerability research across mobile, web, backend, and internal systems.

Your work spans identifying systemic gaps, driving scalable mitigations, and embedding security into the software development lifecycle. You will lead investigations, develop tooling, and mentor peers while collaborating with product and infra teams to enforce robust

Qualifications

• 6+ years in security engineering roles.
• Experience in penetration testing, vulnerability research, or security assessments.
• Threat modeling and security architecture reviews for large-scale software.
• Ability to translate findings into actionable recommendations in writing.
• Experience with security automation and tooling.
• Experience with AI integration and large-scale distributed systems.
• Proficiency in programming languages (Python, C/C++, Java).
• Experience with offensive security techniques (exploits, binary analysis, red team).

Responsibilities

• Conduct security assessments across Meta's web, mobile, and backend systems to identify risks.
• Perform threat modeling and security architecture reviews.
• Identify systemic gaps and drive cross-functional mitigations at scale.
• Develop security tooling, automation, and detection capabilities.
• Collaborate with engineering teams to define security requirements in the SDLC.
• Lead complex security investigations and incident response efforts.
• Translate findings into prioritized recommendations for engineering and leadership.
• Mentor engineers on security best practices and support recruitment.
• Manage oncall security responsibilities and triage issues.
• Identify and land new security initiatives on the team roadmap.

Skills

Security engineering

Penetration testing

Threat modeling

Vulnerability research

Security tooling

Incident response

AI in security

Python

Security architecture

Documentation

Tools

Static analysis tools

Dynamic analysis tools

Red team tools

Cloud security tooling

Job description

Meta is seeking a Security Engineer to protect billions of users and Meta's global infrastructure. You will perform security assessments, threat modeling, and vulnerability research across mobile, web, backend, and internal systems.

Your work spans identifying systemic gaps, driving scalable mitigations, and embedding security into the software development lifecycle. You will lead investigations, develop tooling, and mentor peers while collaborating with product and infra teams to enforce robust