Senior Full-Stack Engineer — Lead Personalization at Scale

Klaviyo Inc.; Boston, Northern (MA, KY); Hybrid; USD 148,000 - 222,000; Full time

Job summary

Klaviyo Inc. in Boston is seeking a Senior Software Engineer for the Customer Hub to lead end-to-end product initiatives. You will develop scalable front-end and back-end solutions, drive architecture decisions, and mentor teammates.

You’ll work in a fast-paced, data-driven environment, emphasizing reliability, performance, and measurable impact. The role offers significant ownership, collaboration across disciplines, and opportunities to influence how ecommerce brands personalize the shopper

Qualifications

• 5+ 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 working with React and related 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.
• Experience using AI effectively in software development and delivery, leveraging AI tools to build smarter systems and ways of working from the ground up.

Responsibilities

• Lead key initiatives to enhance our product offerings and support growth.
• Develop innovative end-to-end solutions using front-end and back-end technologies.
• Deploy well-designed, thoroughly tested solutions that ensure reliability and performance.

Skills

React

Leadership

Code reviews

Agile

Testing

Tools

Python

Django

TypeScript

AWS

Job description

Klaviyo Inc. in Boston is seeking a Senior Software Engineer for the Customer Hub to lead end-to-end product initiatives. You will develop scalable front-end and back-end solutions, drive architecture decisions, and mentor teammates.

You’ll work in a fast-paced, data-driven environment, emphasizing reliability, performance, and measurable impact. The role offers significant ownership, collaboration across disciplines, and opportunities to influence how ecommerce brands personalize the shopper