Senior Security Engineer: AI-First Detection & Response

Klaviyo Inc.; Denver, Northern (CO, KY); Hybrid; USD 142,000 - 212,000; Full time

Job summary

Klaviyo is seeking a Senior Security Engineer to join our Detection & Response team. This is an engineering role spanning the full detection and response lifecycle, building detections, triaging alerts, leading investigations, and automating security workflows.

You will work across enterprise, cloud, and product environments, shaping AI-enabled security tooling, participating in on-call rotations, and mentoring teammates while staying ahead of evolving threats.

Qualifications

• 5+ years of hands-on security experience in modern cloud environments.
• Experience in triaging and responding to cyber threats.
• Experience in large-scale log analysis, incident response and/or digital forensics.
• Experience with centralized security data lakes and SIEM solutions.
• Hands-on experience in writing detections-as-code.
• Solid data querying skills (e.g. SQL, Splunk).
• Familiarity with large-scale data pipelines and data engineering techniques.
• Proficient in programming languages to automate / build (e.g., Python, Go or similar).
• Proven experience with git/GitHub and CI/CD automations.
• Familiarity with tactics, techniques, and procedures used by threat actors.
• Experience being part of detection and response or incident response on-call.
• Engineering-first and AI-first approach for all work performed.
• Strong passion for continuous learning and staying updated on evolving technology.
• Strong oral and written communication skills.
• Team player with a strong, self-managing work ethic.

Responsibilities

• Leverage engineering practices to develop, test, and deploy high-fidelity rule-based and anomaly-based detections-as-code
• Detect and respond to cyber threats using security data lake, SIEM, and cloud platforms
• Respond to alerts, cyber threats, and drive end-to-end incident response investigations
• Perform digital forensic investigations to include collection and analysis of evidence
• Automate and codify detection and response workflows and processes
• Build security tooling to drive automation across D&R lifecycle
• Improve and maintain detection and response pipelines and underlying systems
• Work with Threat Intelligence team to identify and respond to sophisticated threats
• Develop AI-first security systems to automate detection and response operations
• Conduct threat hunts across corporate, cloud and product environments
• Support data engineering workflows for core security data lake and SIEM platforms
• Be an active member of D&R on-call rotations
• Coach and mentor security engineers within the detection & response team

Skills

5+ years hands-on security experience

Threat triage & incident response

Large-scale log analysis

SIEM & security data lake

Detections-as-code

Python or Go

SQL & Splunk querying

Git/GitHub CI/CD

Threat intelligence collaboration

Tools

Git/GitHub

Cloud platforms (AWS/Azure)

Data lakes

Job description

Klaviyo is seeking a Senior Security Engineer to join our Detection & Response team. This is an engineering role spanning the full detection and response lifecycle, building detections, triaging alerts, leading investigations, and automating security workflows.

You will work across enterprise, cloud, and product environments, shaping AI-enabled security tooling, participating in on-call rotations, and mentoring teammates while staying ahead of evolving threats.