Software Engineer II - Events

We love tackling tough engineering problems and look for Engineers who specialize in certain areas but are passionate about building, owning & scaling features end to end from scratch and breaking through any obstacle or technical challenge in their way. We push each other to move out of our comfort zone, learn new technologies and work hard to ensure each day is better than the last.

Klaviyo operates a real-time data platform built for massive scale on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines.

**This role is based in Boston and requires working onsite three days per week**

Software Engineer II — Events

Boston, MA (Hybrid)

Klaviyo’s Core Data Platform is built on three foundational concepts: Profiles, Objects, and Events. Events represent the actions taken by customers’ end users and are the backbone of Klaviyo’s platform — powering segmentation, flows, analytics, and an expanding set of AI-driven features.

About the Role

The Events team owns Klaviyo’s real-time event ingestion and processing platform, one of the highest-scale systems in the company. As a Software Engineer II on the Events team, you’ll help build and operate distributed systems that ingest, validate, transform, and persist billions of events reliably and efficiently.

This role is ideal for engineers who enjoy working on high-throughput, latency-sensitive systems, care deeply about production quality, and want to grow their skills operating large-scale platforms.

How You’ll Make an Impact

• Build and operate real-time event ingestion pipelines used by nearly every Klaviyo feature


• Improve system reliability, performance, and observability in a high-scale environment


• Work on systems that directly power customer-facing automation, analytics, and personalization


• Gain hands-on experience debugging and operating distributed systems in production


• Collaborate closely with engineers across Core Data and product teams

What You’ll Do

• Design, implement, and maintain event ingestion and processing systems


• Deliver well-scoped projects end-to-end with guidance from senior engineers


• Write high-quality, maintainable, and well-tested production code


• Participate in code reviews and technical design discussions


• Help monitor and improve system performance, reliability, and cost efficiency


• Participate in on-call rotations and incident response with mentorship and support


• Work cross-functionally to ensure event data is reliable and usable by downstream systems

What We’re Looking For

Required

• 3–5 years of professional software engineering experience


• Experience building and maintaining production systems and working with databases


• Proficiency in at least one programming language (Python preferred)


• Understanding of distributed systems fundamentals (e.g. concurrency, failure modes)


• Strong debugging and problem-solving skills


• Ability to deliver well-scoped work independently while collaborating effectively with a team

Nice to Have

• Experience with data pipelines, databases,  streaming systems, or real-time processing


• Experience operating systems in a cloud environment (AWS preferred)


• Familiarity with monitoring, alerting, and incident response


• Exposure to high-throughput or low-latency systems

Why Join the Events Team?

• Work on some of the highest-scale systems at Klaviyo


• Solve challenging real-time data problems with real customer impact


• Learn how large distributed systems behave in production


• Grow alongside experienced platform engineers and mentors


• Build foundational infrastructure used across the entire product

Our Engineering Culture

At Klaviyo, we value ownership, curiosity, and continuous improvement. Engineers are encouraged to understand the systems they work on deeply, collaborate openly, and take pride in building software that lasts. You’ll be supported in growing your technical skills while making meaningful contributions from day

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Please see the independent bias audit report covering our use of Covey here