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
Our team is looking for a Senior Full Stack Engineer to help build the future of Customer Agent, Klaviyo’s AI-native conversational platform. In this role, you’ll play a critical part in shaping how autonomous service, AI-driven support, and agentic commerce experiences evolve at scale across millions of customer interactions.
You’ll work across the stack to design, build, and scale systems that power intelligent workflows, conversational experiences, tools integrations, retrieval systems, onboarding flows, observability, and multi-channel customer engagement. You’ll help develop both foundational platform capabilities and customer-facing experiences that enable brands to launch, customize, and continuously improve their own highly-configurable AI agents.
As a Senior Engineer, you’ll tackle complex technical and product challenges, develop multiple solution paths, and evaluate business and architectural trade-offs to determine the best approach. You’ll also act as a technical leader and mentor, driving engineering quality, execution, and decision-making across projects. Additionally, you’ll be responsible for deploying well-designed, thoroughly tested solutions that prioritize reliability, scalability, and customer impact.
The Customer Agent team is building one of Klaviyo’s most ambitious and strategic product areas: an extensible AI platform that enables brands to deliver personalized, autonomous customer experiences across channels like chat, email, SMS, and beyond. We operate with high ownership, rapid iteration cycles, and a strong bias toward execution. Every engineer is expected to think holistically about customer outcomes, collaborate deeply across engineering, product, design, data science, and go-to-market teams, and push beyond traditional role boundaries to help the team move faster.
Success in this role means shipping high-quality systems quickly, contributing to foundational platform decisions, improving the intelligence and reliability of our agent experiences, and helping define how AI-powered customer engagement evolves at Klaviyo.
What We’re Looking For
• A proven track record of building high-quality products and systems, with pride in writing clean, maintainable, high-quality code.
• 7+ years of experience in a software engineering role.
• Strong experience developing end-to-end software solutions or extensive experience across both front-end and back-end technologies.
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