Senior Software Engineer, Composer AI Product

About the Role

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. We own the native chat surface, the agent orchestrator, and the agentic UI framework that other teams across Klaviyo will plug into.

Responsibilities

• Tackle complex technical and product challenges, develop multiple solution paths, and evaluate business and architectural trade-offs to determine the best approach.
• Act as a technical leader and mentor, driving engineering quality, execution, and decision-making across projects.
• Deploy well-designed, thoroughly tested solutions that prioritize reliability, scalability, and customer impact.
• Contribute to foundational platform decisions, improving the intelligence and reliability of our agent experiences, and helping define how AI-powered customer engagement evolves at Klaviyo.

Requirements

• A proven track record of building high-quality products and systems, with pride in writing clean, maintainable, high-quality code.
• 7+ years of experience in a software engineering role.
• Strong experience developing end-to-end software solutions or extensive experience across both front-end and back-end technologies.
• Experience building scalable, customer-facing systems in fast-moving product environments - we operate like a startup inside of Klaviyo.
• 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.
• Excitement about leveraging AI to improve engineering velocity, customer experiences, and operational workflows.
• A strong product mindset and willingness to collaborate cross-functionally to solve ambiguous problems with urgency and pragmatism.

Qualifications

• Nice to have: Skills with Python and related technologies, skills with React and related technologies, experience building conversational AI systems, workflow engines, or agentic platforms, experience with retrieval systems, embeddings, eval frameworks, or LLM orchestration patterns, experience building cloud-native solutions, ideally with AWS, experience developing customer support, commerce, marketing, or customer data software solutions, experience with machine learning systems or AI infrastructure, experience building multi-tenant or highly configurable SaaS platforms, familiarity with observability, tracing, experimentation, or AI quality/evaluation tooling.

Benefits

• 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.
• 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.

Pay

• 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.

Schedule

• 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.

Nice to Have

• Nice to have: Skills with Python and related technologies, skills with React and related technologies, experience building conversational AI systems, workflow engines, or agentic platforms, experience with retrieval systems, embeddings, eval frameworks, or LLM orchestration patterns, experience building cloud-native solutions, ideally with AWS, experience developing customer support, commerce, marketing, or customer data software solutions, experience with machine learning systems or AI infrastructure, experience building multi-tenant or highly configurable SaaS platforms, familiarity with observability, tracing, experimentation, or AI quality/evaluation tooling.