Software Engineer II

Responsibilities

• Implement user-experience improvements across the Klaviyo product to improve new customer onboarding and activation
• Design, implement, and interpret A/B tests to validate ideas and drive iterative product improvements
• Collaborate with marketing, data-science, sales, and engineering teams to discover improvement opportunities
• Engage directly with customers to understand their needs and reduce friction
• Improve experimentation and development processes and mentor other engineers
• Define goals and constraints for AI agents while owning implementation correctness, security, performance, and maintainability

Requirements

• Background in full-stack software engineering with experience building user-facing features, APIs, and infrastructure
• Passion for growing and improving a product using a data-driven mindset
• Experience with A/B testing and metric-based goals to improve user experience (nice to have)
• Experience with or strong willingness to learn AI-driven software delivery practices
• Ability to thrive in a fast-paced, customer-focused, strategic environment

Preferred Qualifications

• Experience with React, TypeScript, Python, and Django
• Familiarity with MySQL, Cassandra, RabbitMQ, Redis, and AWS infrastructure

About the Company

Klaviyo is a world-leading marketing automation platform dedicated to accelerating revenue and customer connection for online businesses through owned channels like email, web, and mobile. The company enables brands to leverage transactional and behavioral data to power highly-targeted customer and prospect communications.