Senior Software Engineer, Customer Agent | Klaviyo Careers

The Briefed; Boston (MA); On-site; USD 148,000 - 222,000; Full time

Benefits offered by this job

Annual bonus & equity

Health & wellbeing benefits

Job summary

Klaviyo is hiring for the Customer Agent team to build an AI-native, scalable platform for autonomous service and agentic commerce. You will work on full-stack systems, tooling integrations, and retrieval systems across multiple channels.

We seek 7+ years of software engineering experience, a track record of shipping high-quality code, and leadership in fast-moving product environments. Strong emphasis on testing, deployment, and collaboration with cross-functional teams.

Qualifications

• 7+ years of software engineering experience.
• Track record of building high-quality products with clean, maintainable code.
• Experience delivering end-to-end solutions or full-stack capability across front-end and back-end.
• Experience building scalable, customer-facing systems in fast-moving product environments.
• Experience leading projects and owning technical and business outcomes.
• Experience mentoring team members and driving team growth.
• Experience with code reviews and robust testing/deployment cycles.
• Practical experience with LLMs, AI tooling, or agentic workflows.
• Strong product mindset and ability to solve ambiguous problems with urgency.

Responsibilities

• Design, build, and scale full-stack systems for intelligent workflows, conversational experiences, tool integrations, retrieval, onboarding flows, and observability.
• Build foundational platform capabilities and customer-facing experiences enabling brands to launch and customize AI agents.
• Weigh architectural and business trade-offs when tackling complex technical challenges.
• Act as a technical leader and mentor to drive engineering quality and decisions.
• Deploy well-designed, thoroughly tested solutions prioritizing reliability and scalability.
• Collaborate with engineering, product, design, data science, and go-to-market teams.

Skills

Software engineering

End-to-end solutions

Mentoring

Code reviews

LLMs tooling

Tools

React

Python

AWS

LLM tooling

Job description

Join the team building Customer Agent, Klaviyo’s AI-native conversational platform for autonomous service, AI-driven support, and agentic commerce at scale. You will work across the stack on intelligent workflows, conversational experiences, tool integrations, retrieval systems, and multi-channel engagement. The Customer Agent team operates like a startup inside Klaviyo, with high ownership and rapid iteration.

Key Responsibilities

• Design, build, and scale full-stack systems for intelligent workflows, conversational experiences, tool integrations, retrieval, onboarding flows, and observability
• Build foundational platform capabilities and customer-facing experiences that let brands launch and customize their own AI agents
• Tackle complex technical and product challenges and weigh architectural and business trade-offs
• Act as a technical leader and mentor, driving engineering quality and decision-making
• Deploy well-designed, thoroughly tested solutions that prioritize reliability, scalability, and customer impact
• Collaborate with engineering, product, design, data science, and go-to-market teams

Requirements

• 7+ years of software engineering experience
• A proven track record of building high-quality products with clean, maintainable code
• Strong experience developing end-to-end solutions or deep experience across front-end and back-end technologies
• Experience building scalable, customer-facing systems in fast-moving product environments
• Experience leading projects and owning technical and business outcomes
• Experience mentoring team members and driving team growth
• Experience with code reviews and maintaining robust testing and deployment cycles
• Practical experience experimenting with LLMs, AI tooling, or agentic workflows
• A strong product mindset and ability to solve ambiguous problems with urgency

Skills

Technical Skills

• Full-stack development (front-end and back-end)
• LLMs, AI tooling, and agentic workflows
• Scalable, customer-facing system design
• Code review, testing, and deployment practices

Soft Skills

• Technical leadership and mentoring
• Cross-functional collaboration
• Product mindset and pragmatism
• Ownership and accountability

Nice to Have

• Python and React
• Experience building conversational AI systems, workflow engines, or agentic platforms
• Experience with retrieval systems, embeddings, eval frameworks, or LLM orchestration
• Cloud-native development, ideally on AWS
• Experience with customer support, commerce, marketing, or customer data software
• Experience with machine learning systems or AI infrastructure
• Experience building multi-tenant or highly configurable SaaS platforms
• Familiarity with observability, tracing, experimentation, or AI evaluation tooling

Job Details

• Location: Not specified (US locations; up to 10% travel for onboarding, team meetings, and events)
• Job Type: ONsite
• Salary: $148,000 - $222,000 USD base (varies by location, skills, and experience)

Benefits

• Annual cash bonus plan, equity, and sign-on payments (based on eligibility)
• Comprehensive health, welfare, and wellbeing benefits