Principal Engineer, Enterprise Scalability (Remote - East Coast Only)

The posting, as Klaviyo wrote it

At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you’re a close but not exact match with the description, we hope you’ll still consider applying. Want to learn more about life at Klaviyo? Visit klaviyo.com/careers to see how we empower creators to own their own destiny.

At Klaviyo, we help businesses build stronger relationships with their customers. As our customers grow, our platform needs to support greater data volumes, more demanding workloads, and increasingly complex operations—with the performance and reliability they depend on.

Engineering at this scale takes technical depth, sound judgment, and close collaboration. You’ll work across teams to solve challenging problems, turn architectural improvements into production results, and help build a platform ready for our largest customers.

Your Impact

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.

You will identify and remove major bottlenecks, drive platform-wide architectural changes, and establish clear measures of readiness for our largest tenants and most demanding workloads. Your work will span system design, profiling, implementation, and production rollout. You will also help teams adopt practical tools and repeatable patterns that make performance and reliability part of everyday engineering.

This role suits an experienced engineer who can move between deep technical investigation and clear executive communication, make and defend architectural decisions, and build alignment across teams.

Reports to: VP of Engineering
Direct reports: None

Location: Remote (Only applicable to candidates outside of MA. Requires travel to Boston HQ at least once per quarter)

What You’ll Do

Define what scale readiness means. Establish measurable targets for latency, throughput, error rates, and capacity. Build a shared scorecard and align teams on service-level objectives, error budgets, and performance expectations for critical enterprise workloads.

Remove the bottlenecks that matter most. Use production data, profiling, and reproducible benchmarks to identify constraints. Partner with service owners to implement fixes and verify improvements under representative workloads.

Drive architectural change. Design and implement sharding, partitioning, caching, back-pressure, and workload isolation strategies. Advance multi-region readiness and build safe paths for high-volume data
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n ecommerce and beyond. To reach our goals, we need our own crew of remarkable creators—ambitious and collaborative teammates who stay focused on our north star: delighting our customers. If you’re ready to do the best work of your career, where you’ll be welcomed as your whole self from day one and supported with generous benefits, we hope you’ll join us.

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