Software Engineer

As a Senior Software Engineer on the team, you’ll play a key role in designing and building scalable systems that power how customers manage and activate their data. Partnering closely with product managers, data scientists, and other platform teams, you’ll help define scope, translate complex data and UX problems into practical implementations, and build intuitive workflows that give customers confidence in their audiences. This role leans frontend, with a strong focus on crafting thoughtful, reusable components and seamless user experiences using technologies like TypeScript, React, Python, and Django. There are ample opportunities for growth given the scope of this role and the team’s central role in Klaviyo’s product.

How You Will Make a Difference:

• You will be a core member of the PLS team, working on impactful customer-facing features that will make our product the best in the industry.
• You will work on creating easy-to-use editors that are highly performant.
• You will work closely with Product, Design, and Data Science to provide the best experience for our customers.
• You will mentor team members and drive initiatives that help the team learn new skills.

• 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

Technologies We Use (not exhaustive):

• React, TypeScript, Redux
• Python, Django
• Amazon Web Services (EC2, RDS, Aurora, S3, etc.), Terraform, and other DevOps tools
• MySQL, RabbitMQ, Redis, ProxySQL

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. Base Pay Range For US Locations: $148,000-$222,000 USD

This role may require up to 10% travel for purposes such as new hire onboarding, client or partner work if applicable, team meetings, and industry events. Travel is coordinated in advance.

Get to Know Klaviyo

We’re Klaviyo (pronounced clay-vee-oh). We empower creators to own their destiny by making first-party data accessible and actionable like never before. We see limitless potential for the technology we’re developing to nurture personalized experiences in ecommerce and beyond. To reach our goals, we need our own crew of remarkable creators-ambitious and collaborative teammates who stay focused on our north star: delighting our customers. If you’re ready to do the best work of your career, where you’ll be welcomed as your whole self from day one and supported with generous benefits, we hope you’ll join us.

AI fluency at Klaviyo includes responsible use of AI (including privacy, security, bias awareness, and human-in-the-loop). We provide accommodations as needed.