[Hiring] Principal Engineer, Enterprise Scalability @Klaviyo

Role Description

We are seeking a senior technical leader to own Klaviyo’s approach to enterprise scalability, performance, reliability, and multi-region readiness. Reporting to a VP of Engineering, you will be a senior individual contributor with no direct reports. You will lead through technical expertise, hands-on engineering, and influence, partnering across teams to deliver improvements that matter to our customers.

• Identify and remove major bottlenecks.
• Drive platform-wide architectural changes.
• Establish clear measures of readiness for our largest tenants and most demanding workloads.
• Work spans system design, profiling, implementation, and production rollout.
• Help teams adopt practical tools and repeatable patterns that make performance and reliability part of everyday engineering.

What You’ll Do

• Define what scale readiness means.
• Establish measurable targets for latency, throughput, error rates, and capacity.
• Remove the bottlenecks that matter most.
• Drive architectural change.
• Make scale engineering repeatable.
• Build readiness into delivery.
• Turn incidents into lasting improvements.
• Apply AI where it improves outcomes.
• Connect engineering decisions to customer needs.

Qualifications

• Deep experience scaling multi-tenant SaaS.
• Strong performance and distributed systems expertise.
• Engineering depth from diagnosis through delivery.
• Sound technical judgment.
• Leadership across organizational boundaries.
• Clear communication.
• Practical AI fluency.

Requirements

• 12+ years of relevant engineering experience.
• Hands-on experience with performance engineering, capacity planning, sharding and partitioning, caching, back-pressure, tenant isolation, multi-region architectures, and large-scale migrations.
• Ability to investigate unfamiliar systems, test hypotheses, write production code, and work with service owners to roll out changes safely.
• Ability to align teams around shared outcomes and clarify ownership.
• Experience in explaining complex technical decisions and their business implications.
• Experience applying AI tools or automation to engineering work.

What Success Looks Like in 6–12 Months

• A company-wide scale scorecard is adopted and reviewed regularly.
• Two to three high-impact bottlenecks are removed.
• Our largest customer workloads show measurable improvements in tail latency, throughput, and error rates.
• Multi-region readiness and high-volume migration plans have clear priorities.
• Teams use shared benchmarks and readiness checks to catch regressions earlier.
• AI-assisted tools demonstrate measurable value in investigation or incident response.

Benefits

• Participation in the company’s annual cash bonus plan.
• Variable compensation (OTE) for sales and customer success roles.
• Equity and sign-on payments.
• A comprehensive range of health, welfare, and wellbeing benefits based on eligibility.

Company Description

Klaviyo empowers creators to own their destiny by making first-party data accessible and actionable. We see limitless potential for the technology we’re developing to nurture personalized experiences in ecommerce and beyond.