Sr. Staff Engineer - Customer Agent

At Klaviyo, we value the unique backgrounds, experiences and perspectives each team member brings to our workplace. We believe everyone deserves a fair shot at success and appreciate experiences beyond traditional job requirements.

About The Role

We are seeking an experienced Senior Staff Engineer with deep expertise building and scaling agentic systems and AI-enabled products. You will shape how Customer Agent evolves into a highly extensible, reliable, and intelligent platform. You will drive technical strategy, lead architectural direction, and partner closely with product, design, data science, and engineering leaders to deliver industry-defining AI experiences.

This role is ideal for a hands-on technical leader who thrives in ambiguity, enjoys building from first principles, and wants to influence both product direction and engineering strategy. You will operate as a force multiplier across teams, leading through technical excellence, execution, and mentorship rather than direct people management. You will work on some of Klaviyo’s most important AI investments, helping define the next generation of conversational experiences while operating at the intersection of large-scale systems, agentic workflows, personalization, and real-world customer outcomes.

Responsibilities

• Lead the architecture, design, and implementation of Customer Agent’s core platform and AI capabilities.
• Drive technical strategy and long-term system evolution for conversational AI experiences serving millions of users.
• Build and ship complex AI-powered product features, balancing speed, quality, reliability, and customer impact.
• Partner closely with Product, Design, Data Science, GTM, and Engineering leaders to define product direction and execution plans.
• Make critical technical decisions around agent architectures, orchestration frameworks, retrieval systems, memory, tool use, evaluation, and reliability.
• Establish engineering best practices around observability, testing, monitoring, experimentation, and operational excellence for AI systems.
• Lead large, cross-functional initiatives spanning multiple teams and organizations.
• Mentor engineers through technical leadership, design reviews, architecture discussions, and hands-on collaboration.
• Evaluate emerging AI technologies and frameworks, identifying opportunities to create meaningful customer value.
• Influence engineering standards and contribute to the broader technical direction of Klaviyo’s AI platform.

Requirements

• 10+ years of software engineering experience building and operating production systems at scale.
• Significant experience designing and shipping customer-facing AI-powered products or agentic systems.
• Strong backend engineering and distributed systems fundamentals, with the ability to reason about scale, latency, reliability, and operational tradeoffs.
• Demonstrated expertise with modern AI architectures, including LLM-powered applications, retrieval systems, agent workflows, orchestration, evaluation frameworks, and guardrails.
• Proven ability to lead complex, multi-quarter technical initiatives involving multiple teams and stakeholders.
• Strong product instincts and the ability to connect technical decisions to customer and business outcomes.
• Comfortable operating in ambiguous, fast-moving environments and defining direction when requirements are incomplete.
• Excellent communication and collaboration skills across engineering, product, design, and executive audiences.
• Hands-on builder who enjoys working directly in code and tackling difficult technical problems.
• Track record of influencing engineering organizations through technical leadership, mentorship, and execution excellence.

Skills

• Experience building conversational AI, customer support automation, or agentic workflow platforms.
• Experience with production evaluation systems, AI observability, human-in-the-loop workflows, and reliability engineering for LLM-powered products.
• Experience building 0→1 products or working in startup environments.

Pay

Base Pay Range for US Locations: $216,000—$324,000 USD. The base salary offered is determined by several factors, including job-related skills, relevant experience, education or training, and work location. In addition to base salary, total compensation 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.

Schedule

This is an in-office role based in Boston, MA. The 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.

Klaviyo empowers creators to own their destiny by making first-party data accessible and actionable. We see limitless potential in the technology we’re developing to nurture personalized experiences in ecommerce and beyond. Our team is collaborative, ambitious, and focused on delighting our customers.