Software Engineer II - Channel Rendering and Engagement

About this role

*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.*

### About the Role

Klaviyo is looking for a Backend Engineer to support key initiatives that enhance our product offerings and drive company growth. In this role, you'll play a critical part in delivering end-to-end solutions using cutting-edge distributed systems and AI technologies. You’ll improve existing products and develop new capabilities that push the boundaries of what’s possible for our customers.

As a Software Engineer II, you’ll tackle complex challenges, explore multiple solutions, and weigh business and technical trade-offs to determine the best path forward. You’ll actively contribute to team discussions and help shape important technology decisions. You'll also be responsible for shipping well-designed, thoroughly tested solutions that prioritize reliability and performance.

The Channel Rendering & Engagement team builds and runs the core infrastructure that turns Klaviyo’s templates and data into the actual messages customers receive - across email, SMS, push, and previews - at massive scale and low latency. We own the high‑performance rendering pipeline, engagement tracking, and compliance-related services. These services collectively ensure that messages are delivered quickly, reliably, and safely. We are the team that guarantees every personalized message is rendered correctly, tracked accurately, and meets strict SLOs, so the rest of Klaviyo can innovate on top of a rock-solid communications platform.

We work cross-f...