Security Engineer

Responsibilities

• Own security incidents from scoping through containment, forensics, write-up, and remediation follow-through.
• Write, tune, test, measure, version-control, review, and retire detection content.
• Build incident-response playbooks, integrations, and workflows that eliminate repeated manual work.
• Track relevant threat activity and convert intelligence into detections, hunts, and hardening initiatives.
• Contribute to hypothesis-led threat hunting and handle escalations surfaced by the triage pipeline.
• Build and improve agents, prompts, and enrichment logic supporting the AI-assisted triage pipeline.
• Provide feedback that improves the triage pipeline.

Requirements

• Hands-on security operations experience with incidents that can be explained in detail.
• Proficiency in Python or an equivalent scripting language and a preference for solving recurring problems with code.
• Working knowledge of detection logic, log pipelines, and telemetry from EDR, identity, cloud, network, and SaaS sources.
• Ability to define outcomes for ambiguous problems and build solutions independently.
• Clear written communication for incident timelines, design notes, and postmortems.
• GCP and/or AWS experience, including cloud logging, IAM, and cloud-specific failure modes, is preferred.
• Experience with Tines or n8n and judgment about when to move a workflow into production code is preferred.
• Agent programming, prompt engineering, and reliable operational LLM tooling experience are preferred.
• Experience with AI-enriched detection or triage pipelines is preferred.

Benefits

• Fully remote outside a 30-mile radius of a Five9 office; hybrid within that radius with three office days per week on Tuesday, Wednesday, and Thursday.
• The role requires working Pacific Time hours from 9:00 AM to 5:00 PM.
• Health, dental, and vision coverage begins on the first day, with Five9 covering 100% of the employee portion and sharing a high portion of dependent costs.
• Short- and long-term disability, basic life insurance, and a 401(k) savings plan with employer matching are provided.
• Mental health support platform access is available for covered employees and dependents.
• Generous employee stock purchase plan, paid time off, company-paid holidays, paid volunteer hours, and 12 weeks of paid parental leave are offered.