Senior Software Engineer - Infrastructure Security New Boston, MA

Senior Software Engineer - Infrastructure Security Engineering – Boston, MA Team Overview The Infrastructure Security team makes it simple and easy for engineers to make secure choices while developing world‑class software at high speed. Security is built in by default—seamless and effortless—making engineers’ lives better and Klaviyo more secure. Our work sits at the intersection of security, infrastructure, and software engineering. We build cloud‑native platforms and services that are reliable, secure, and performant at global scale, forming the foundation that Klaviyo engineers rely on every day. This role is for engineers who enjoy building modern distributed systems, care about security and reliability, and want to have real impact across a large engineering organization. How you’ll make an impact Design, build, and maintain cloud‑native security services used across Klaviyo Own meaningful components and services end to end, from implementation through production operation Improve the availability, scalability, latency, and efficiency of infrastructure security systems Collaborate with senior engineers on system design and architecture, contributing ideas and technical solutions Identify performance, reliability, and security issues in distributed systems and drive improvements Work extensively with technologies such as Python, Golang, AWS, Kubernetes, Terraform, and modern data stores Participate actively in design reviews, code reviews, and whiteboarding sessions Contribute to operational excellence through monitoring, alerting, and incident response Participate in an on‑call rotation with a focus on learning, prevention, and reducing operational toil Build tooling, automation, and documentation that improve developer experience and security posture Partner with product‑facing and platform engineers to ship impactful, secure solutions Who you are You have 6+ years of solid experience building and operating cloud‑native, distributed systems in production You are comfortable writing production‑quality code in a language such as Python or Go You have hands‑on experience with AWS (or a similar cloud provider) and understand managed services, networking, and IAM concepts You have experience working with containers and orchestration platforms such as Kubernetes You have experience writing infrastructure as code using languages such as Terraform You are comfortable owning services and features independently, while knowing when to ask for feedback or support You understand the fundamentals of scalable, multi‑tenant architectures and secure system design You care about reliability, performance, observability, and security—not just shipping features You are comfortable participating in on‑call and responding to production issues You are an excellent communicator and collaborator. You lead technical discussions at the project and product‑area level, write clear technical design documents and RFCs, and keep stakeholders aligned on progress, risks, and trade‑offs. Ability to handle yourself and complex systems in outage situations and to drive failures to root cause analysis and prevention of future issues. You’ve already experimented with AI in work or personal projects, and you’re excited to dive in and learn fast. You’re hungry to responsibly explore new AI tools and workflows, finding ways to make your work smarter and more efficient. You question convention and proactively look for ways to improve, whether that’s workflows, architecture, tooling, or team processes. You are intrinsically motivated to drive incremental and step‑change improvements that deliver value to the business. You mentor and support other engineers, offering thoughtful feedback in design and code reviews, helping refine specifications, and investing in the growth of more junior engineers on the team. You enjoy working on small, autonomous, agile teams, shipping early and often, pairing with product managers, business stakeholders, and other engineers to craft better software. Nice to have Experience building security tooling, working with security infrastructure systems like Vault, AWS IAM, WAFs, and more Experience with service meshes, API gateways, or zero‑trust architectures Experience improving performance in distributed systems or debugging complex multi‑service workflows Tech Stack Core technologies include: Python / Django / Golang / FastAPI MySQL / Redis / Memcached RabbitMQ / Celery / Apache Kafka / Apache Pulsar AWS / Terraform / Kubernetes Location & Work Model This role is based in Boston, Massachusetts . Klaviyo supports work authorization and relocation for this position. Equal Opportunity & Non‑Discrimination Klaviyo is committed to a policy of equal opportunity and non‑discrimination. We do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law. Compensation & Benefits Base Pay Range for U.S. Locations: $148,000 – $222,000 USD Additional compensation may include participation in annual cash bonus plan, variable compensation, equity, sign‑on payments, and a comprehensive range of health, welfare, and wellbeing benefits as eligible. Travel may be required up to 10% for onboarding, client or partner work, team meetings, or industry events. Travel is coordinated in advance. #J-18808-Ljbffr Klaviyo Inc.