Senior Full Stack Engineer

Senior Software Engineer - New Product at Klaviyo 4 days ago – Be among the first 25 applicants 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 careers.klaviyo.com 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 lead key initiatives that will enhance our product offerings and support our company’s growth. In this role, you’ll play a crucial part in shaping outcomes by developing innovative end-to-end solutions using both front‑end and back‑end technologies. You’ll optimize existing products and create new solutions that redefine what’s possible for our customers. As a Senior Engineer, you’ll tackle complex challenges, develop multiple solutions, and evaluate business and technical trade-offs to determine the best path forward. You’ll also act as a leader and mentor, and drive key technology decisions. Additionally, you’ll be responsible for deploying well‑designed, thoroughly tested solutions that ensure reliability and performance. The New Products team drives Klaviyo’s most ambitious innovations—creating and scaling the company’s boldest new bets. As a nimble group with a flat structure and fast‑moving culture, we prioritize simplicity, speed, and impact. Every team member is expected to take radical ownership—rolling up their sleeves, collaborating across disciplines, and pushing beyond traditional role boundaries to make things happen. Success in this role means delivering exceptional work that sets the standard for velocity and results company‑wide, while helping shape Klaviyo’s future through experimentation, creativity, and executional excellence. What We’re Looking For A proven track record of building high‑quality products and systems, with pride in writing clean, high‑quality code. 7+ years of experience in a software engineering role. Strong experience developing end‑to‑end software solutions or extensive experience with both front‑end and back‑end technologies. Experience leading projects and being accountable for their outcomes. Experience mentoring team members or driving initiatives that help the team learn new skills. Experience conducting code reviews and running a robust testing cycle. Experience working in agile, fast‑paced environments. You’ve already experimented with AI in work or personal projects, and you’re excited to dive in and learn fast. You’re hungry to responsibly explore new AI tools and workflows, finding ways to make your work smarter and more efficient. Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up. Nice to Have Skills with Python and related technologies Skills with React and related technologies Experience developing digital marketing or customer data software solutions. Experience with machine learning. Experience building cloud‑native solutions, ideally with AWS. Base Pay Range For US Locations $152,000—$228,000 USD Equal Opportunity Statement Klaviyo is committed to a policy of equal opportunity and non‑discrimination. We do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law. #J-18808-Ljbffr