Software Engineer II - Social Team

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 Full Stack Engineer to join the Social team and help turn social conversations into long‑term customer relationships. In this role, you'll build end‑to‑end experiences that connect channels like Instagram DMs to Klaviyo’s core platform—capturing high‑intent profiles, consent, and engagement data from social traffic. As a Software Engineer II, you’ll tackle complex technical challenges, explore multiple solution paths, and weigh business and technical trade‑offs to determine the best approach. You’ll contribute actively to design discussions, help shape architectural decisions, and ship well‑designed, thoroughly tested features that prioritize reliability, performance, and a great user experience. On the Social team, we focus on crafting intuitive, high‑impact surfaces that make it easy for brands to grow their lists from social. This includes the experiences that power Instagram auto‑replies and future social entry points, the supporting APIs and services that ingest and transform social events, and the data and analytics that show customers how social programs drive profile growth and revenue. We partner closely with teams across messaging channels, onsite experiences, and profiles to create a cohesive, multi‑channel growth engine. Collaboration is central to how we work. You’ll work with engineers, product managers, designers, and data partners across Klaviyo, gaining exposure to many parts of the stack and product. This keeps the work varied and gives you opportunities to see your code in action across different surfaces—from customer storefronts to internal analytics tools. Looking ahead, Social is expanding beyond our first Instagram auto‑reply experiences into a broader social growth platform. We’ll be deepening our native social integrations, building smarter targeting and personalization based on profile and event data, and creating new ways to route social traffic into high‑conversion destinations like landing pages and onsite modules. Our goal is to make Social not just a feature, but a growth platform that helps brands turn every conversation into a durable customer relationship. What We’re Looking For A proven track record of building high-quality products and systems, with a focus on writing clean, maintainable code 3+ years of experience in a software engineering role Experience building end-to-end software solutions or deep experience with both front-end and back-end technologies Familiarity with code reviews and leading or participating in robust testing practices Experience working in agile, fast-paced environments Nice to Have Experience with Python and related technologies Experience with React and related technologies Background in digital marketing or customer data software Exposure to machine learning concepts or applications Experience building cloud-native solutions, ideally on AWS We use Covey as part of our hiring and / or promotional process. For jobs or candidates in NYC, certain features may qualify it as an AEDT. As part of the evaluation process we provide Covey with job requirements and candidate submitted applications. We began using Covey Scout for Inbound on April 3, 2025. Please see the independent bias audit report covering our use of Covey here Massachusetts Applicants: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An empl ... (truncated, view full listing at source)