Senior Security Engineer

Who you are

• 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

What the job involves

• 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
• 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
• This position will require you to be available during core business hours and support an on-call rotation

The application process

• Posting Open Date: October 6, 2026
• Anticipated Posting Close Date*: December 6, 2026

Benefits

• Parental support and beyond: We support our families by offering generous time off for parental leave. And beyond that, we work hard to build a culture that allows for all employees to have the life outside work that they desire year round.
• Health and wellness: Your well-being matters here. Our health plans offer a variety of options, including full medical, dental, and vision coverage, short- and long-term disability insurance, mental health resources, and more.
• Invest in your future: We offer 401(k)/retirement plans, employee stock purchasing plans (ESPP), and reimbursements for learning and development programs — so we can support your ongoing growth and success.
• Keep learning and growing: Helping people go further means nurturing their talent. Through annual reimbursements for employee learning activities, regular hangouts and advice from our Senior Staff, talks from industry leaders, and cultural events — we offer tons of opportunities for people to learn. And we’re always looking to grow as a company, too: we collect employee engagement and experience data annually and leverage our Employee Experience Champion Network to understand employee feedback, so we can keep improving.