Senior Software Engineer - Growth

Klaviyo Klaviyo · Enterprise · Boston, MA · Engineering

Senior Software Engineer on the Product Expansion/Activation team focused on improving the early customer experience, driving technical design, leading implementation of user-experience improvements, owning the end-to-end experimentation process, and mentoring other engineers. The role involves defining architectural approach and technical strategy, including leveraging AI agents in delivery. Requires extensive full-stack experience, data-driven mindset, and experience with AI-driven software delivery practices.

What you'd actually do

  1. In this role, you will drive the technical design and lead the implementation of high-impact user-experience improvements across the Klaviyo product, focusing on areas critical to new customer success and adoption. You will own the entire project lifecycle, working through ambiguity and requirements refinement to execution and delivery.
  2. You will own the end-to-end experimentation process, including contributing to the definition of strategy, architecting and implementing A/B tests to validate product hypotheses, and interpreting data to drive significant iterative improvements. You will be accountable for the quality and operational health of the features you deliver.
  3. You will serve as a technical leader and liaison, collaborating proactively with partners across teams to define and prioritize key technical initiatives to shape the long-term product roadmap.
  4. You will take a lead role in mentoring and providing technical guidance to other engineers on the team, elevating our experimentation, development, and operational practices, ensuring contributions consistently leave the product area better than when you found it.
  5. You will define the architectural approach and technical strategy for your area of responsibility, anticipating scalability and reliability needs, including leveraging AI agents in our work and delivery, ensuring the solution is robust, scalable, and adheres to best practices for security, performance, and maintainability.

Skills

Required

  • extensive background in full stack software engineering
  • deep understanding of Klaviyo’s systems
  • ability to architect, deliver, and maintain software with an emphasis on high-scale, user-facing features, and their supporting APIs and infrastructure
  • demonstrated ability to drive technical strategy and improvement using a data-driven mindset
  • demonstrated technical experience in using and championing AI-driven software delivery practices and methods
  • ability to work productively through others to set them up for project success

Nice to have

  • Experience driving A/B testing strategies for products with metric-based goals to significantly improve user experience, customer acquisition, and success is a _strong_ plus.

What the JD emphasized

  • leveraging AI agents in our work and delivery
  • using and championing AI-driven software delivery practices and methods