Senior Security Engineer - Detection Engineering

Senior Security Engineer, Detection Engineering

As a Senior Security Engineer on our Detection Engineering team, you will build the detections that catch malicious activity across the Fastly environment and drive the investigations that follow. We are looking for a teammate with a strong security engineering foundation and hands-on experience in security incident response, detection development, and applying AI to security operations. In this role, you will design and build AI agents and automations to support detection and response, develop advanced detections, perform threat hunts, and lead security investigations.

What You'll Do

• 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.

What We're Looking For

• 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.

Preferred Qualifications

• 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.

Work Hours & Location

• Core business hours and on-call rotation support required.
• Hybrid preference near local offices in New York, NY; San Francisco, CA; or Denver, CO (remote within the US also considered).

Interview Process Rules

• The use of AI technologies—including real-time transcription tools, automated scripts, AI copilots, or external assistants—is strictly prohibited during the interview process unless explicitly authorized in advance.