Senior Security Engineer

Klaviyo•Denver, CO

61d

About The Position

As a Senior Security Engineer, you'll be a vital part of the Infrastructure Security Team, focusing on strengthening the security posture across Klaviyo's entire technology environment. Unlike roles with a narrowly defined specialty, this position offers the opportunity to demonstrate your unique expertise-whether that's in cloud security, identity and access management, data protection, secure systems design, or other security domains. Your work will involve evaluating and hardening our infrastructure, collaborating with cross-functional teams, and leveraging AI to build scalable solutions to address emerging threats. We are looking for someone who is excited to bring their specialized skills to the team, shaping Klaviyo's security practices and helping us continue to raise the bar.

Requirements

Have 3+ years of experience in infrastructure or security engineering roles, with deep knowledge in one or more security focus areas (e.g., cloud security, IAM, endpoint security, data protection, detection engineering, compliance)
Comfortable navigating ambiguity and defining priorities in a broad-scoped role
Experienced working in modern cloud environments such as AWS, GCP, or Azure
Familiar with infrastructure-as-code tools such as Terraform, CloudFormation, or Pulumi
Proficient in secure systems design, threat modeling, and vulnerability management
AI Agentic development and prompt engineering, MCP (AWS Bedrock, OpenAI, Anthropic)
Able to clearly articulate complex security topics to technical and non-technical stakeholders
Passionate about security, eager to learn from others and share your expertise

Nice To Haves

certifications (e.g., CISSP, CKS, GCP/AWS Security certs) or equivalent practical experience

Responsibilities

Secure Klaviyo's infrastructure by designing, implementing, and maintaining scalable security controls across cloud, on-prem, and hybrid environments
Evaluate and improve security configurations and policies across a range of technologies, using your domain expertise to reduce risk and enable secure-by-default architectures
Collaborate with engineering and IT teams to embed security practices across the development and deployment lifecycle
Lead threat modeling, risk assessments, and architecture reviews in areas aligned with your specialty
Develop automated solutions and infrastructure-as-code to drive consistent and reproducible security outcomes
Stay ahead of the latest threats and advocate for innovative security solutions aligned with business needs
Help define security standards and best practices at Klaviyo, championing their adoption across teams

Stand Out From the Crowd

Upload your resume and get instant feedback on how well it matches this job.

Upload and Match Resume