Senior Software Engineer - Profiles, Lists and Segments

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 cl...

Why You Should Join the PLS (Profiles, Lists and Segments) Team:

The PLS team is responsible for building and scaling the core customer data experiences at Klaviyo — profiles, lists, and real-time segments. We own the tools that let customers understand who their users are, group them into meaningful audiences, and keep those audiences up to date as new data flows in. Our work un...

5+ years of experience in full-stack development with strong hands-on skills in React, Redux, JavaScript, HTML, and CSS, along with familiarity with general web best practices.
Has a track record of delivering and shipping work powered by or accelerated through AI.
Experience conducting code reviews and running a robust testing cycle using automated testing practices and frameworks, including end-to-end and integration tests (e.g., cypress, pytest).
Experienced with RESTful and GraphQL APIs, and evolving APIs and data models to support product success.
You take ownership of your work—from requirements and edge cases to implementation and testing—and are motivated by solving tough problems with others.
Proven track record of leading complex, multi-quarter projects involving cross-team collaboration and being accountable for their outcomes
React, TypeScript, Redux
Python, Django
Amazon Web Services (EC2, RDS, Aurora, S3, etc.), Terraform, and other DevOps tools
MySQL, RabbitMQ, Redis, ProxySQL
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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 employer who violates this law shall be subject to criminal penalties and civil liability.
Our salary range reflects the cost of labor across various U.S. geographic markets. The range displayed below reflects the minimum and maximum target salaries for the position across all our US locations. The base salary offered for this position is determined by several factors, including the applicant’s job-related skills, relevant experience, education or training, and work location.
In addition to base salary, our total compensation package may include participation in the company’s annual cash bonus plan, variable compensation (OTE) for sales and customer success roles, equity, sign-on payments, and a comprehensive range of health, welfare, and wellbeing benefits based on eligibility. 
Your recruiter can provide more details about the specific salary/OTE range for your preferred location during the hiring process.