Senior Security Engineer - Detection Engineering

Fastly operates an edge cloud platform that helps customers create digital experiences by processing, serving, and securing applications close to end users. The Senior Security Engineer, Detection Engineering will develop advanced threat detections, build AI agents and automations for security operations, conduct threat hunts, and lead complex security investigations.

Responsibilities:

• Develop detections and other analytics to identify threats across cloud, container, corporate, and edge environments
• Lead security investigations, analyzing complex log sources and telemetry to determine root cause
• Build AI agents and automations that speed up detection development, triage, and incident response
• Research, evaluate, implement, and maintain a variety of custom and commercial security tools, such as EDR, SOAR, and SIEM
• Conduct threat hunts to discover unknown malicious activity across our environment
• Participate in our on-call rotations

Requirements:

• Direct experience integrating AI tools, LLMs, and automated agents into security operations workflows to accelerate alert triage, contextualize telemetry, and speed up incident response
• Experience developing, testing, and tuning detections using a detections-as-code approach, including version control and CI/CD
• Proven track record of leading complex security incident investigations, with deep expertise in log analysis, real-time containment, and collecting forensic artifacts
• Strong coding skills in Python or another general-purpose language, with experience building automations for detection and response
• In-depth knowledge of major public cloud platforms (e.g., AWS or GCP) and Linux environments, including containers (e.g., Kubernetes), along with their native logging and security tooling
• Solid grasp of attacker tactics and techniques, with experience in threat hunting or threat modeling to guide detection priorities
• Familiarity with content delivery networks (CDN), edge cloud platforms, or Fastly products and services
• Experience designing and maintaining scalable ETL processes and data pipelines to ingest, transform, and normalize security telemetry for large-scale analysis
• Experience deploying AI agents in production to detect threats, enrich alerts, and automate response