Klaviyo

Senior Software Engineer, Composer AI Product

Boston, MA · Senior

Sponsorship not specified$148k-$222kDetected 20 days ago

PythonReactCode ReviewMachine LearningLLMsAI OrchestrationA/B TestingOnboardingCustomer SuccessCustomer SupportMentoring

About the role

By joining the Klaviyo Conversational AI Platform team, you will have the opportunity to have a direct impact on over 170,000 brands that use Klaviyo every day to engage with their customers.
You'll also act as a technical leader and mentor, driving engineering quality, execution, and decision-making across projects.
Success in this role means shipping high-quality systems quickly, contributing to foundational platform decisions, improving the intelligence and reliability of our agent experiences, and helping define how AI-powered customer engagement evolves at Klaviyo.

Visit klaviyo.com/careers to see how we empower creators to own their own destiny.
an ecosystem of LLM‑powered agents that can analyze, create, and optimize marketing programs across campaigns, flows, forms, and more.
As a Senior Engineer, you'll tackle complex technical and product challenges, develop multiple solution paths, and evaluate business and architectural trade-offs to determine the best approach.
Additionally, you'll be responsible for deploying well-designed, thoroughly tested solutions that prioritize reliability, scalability, and customer impact.
You'll also help define and build Klaviyo's Autonomous Marketing platform: an ecosystem of LLM‑powered agents that can analyze, create, and optimize marketing programs across campaigns, flows, forms, and more.

7+ years of experience in a software engineering role.
Experience leading projects and being accountable for technical and business outcomes.
Experience mentoring team members or driving initiatives that help the team grow and learn new skills.
Experience conducting code reviews and maintaining a robust testing and deployment cycle.
Curiosity and enthusiasm for AI-native product development, including practical experience experimenting with LLMs, AI tooling, or agentic workflows in professional or personal projects.

Skills with Python and related technologies.
Skills with React and related technologies.
Experience with retrieval systems, embeddings, eval frameworks, or LLM orchestration patterns.
Familiarity with observability, tracing, experimentation, or AI quality/evaluation tooling.
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.

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.
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.
Our salary range reflects the cost of labor across various U.S. geographic markets.

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.
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.

The Klaviyo Composer team is building the foundation for how Klaviyo customers plan, create, edit, and iterate on their marketing strategy through an in‑app, AI‑powered conversational experience.
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 do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability

This listing is sourced directly from Klaviyo's careers page and normalized into a canonical job model.