AI Engineer I

Klaviyo Campus; Boston (MA); On-site; USD 104,000 - 156,000; Full time

Job summary

Klaviyo seeks an AI Engineer to design and build scalable backend systems powering our AI products and agent solutions. You will partner with ML engineers and software engineers to deliver impactful, production-ready AI features.

Ideal candidates are pursuing an advanced CS/AI degree and have hands-on experience deploying generative AI and agentic AI applications in production environments, with a strong Python and backend framework background.

Qualifications

• Hands-on experience building and deploying generative AI and agentic AI applications into production.
• Proficiency in Python and modern backend frameworks (FastAPI, Django).
• Experience creating human and automated evals to ensure AI model quality.
• Thrives in a fast-moving startup-like environment.

Responsibilities

• Design and build backend systems that scale AI solutions for 200K+ customers.
• Develop robust, reliable services to serve AI models in production.
• Contribute to evolving agentic architecture and improve AI agents’ performance.
• Collaborate with product managers and ML engineers to drive impact.
• Stay updated on AI trends and apply them within Klaviyo’s ecosystem.

Skills

Python

FastAPI

Django

Generative AI

Agentic AI

Orchestration

RAG

Safety guardrails

Model evaluation

Education

Pursuing advanced degree in CS/AI

Tools

FastAPI

Django

Job description

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 believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you’re a close but not exact match with the description, we hope you’ll still consider applying.

At Klaviyo, we believe the future of software lies not in productivity tools for human users but in software that can run and optimize itself based on outcome or reward metrics. We’ve built the infrastructure and application that serve as the interface between businesses and consumers. We now have over 200,000 customers, billions of consumer profiles, and hundreds of billions of customer messages and follow‑on conversion data. We have a big opportunity to build state‑of‑the‑art AI and machine learning technologies at Klaviyo to power our products and develop AI agents that can automatically create and execute marketing or customer experiences, strategies, and campaigns for any business.

About the role

At Klaviyo, our Engineering team builds the foundational technologies that power how brands grow through owned marketing. As an AI Engineer at Klaviyo, you’ll play a key role in designing and building scalable backend systems and user experiences that power our AI products and AI agent solutions. You’ll partner closely with product managers, machine learning engineers, and software engineers, to drive real‑world impact at scale. This is a backend‑heavy role with opportunities to influence architecture, async processing pipelines, distributed systems, and more.

This is an opportunity to apply your generative AI and agentic AI application skills in a production environment. You’ll be embedded within one of our engineering teams and work on meaningful projects that help customers interact with powerful marketing tools, all while building a strong technical foundation and connections across Klaviyo.

Early career talent comes to Klaviyo with experience in a variety of technical skills, but they are all passionate about building, owning and scaling features end‑to‑end from scratch and breaking through any obstacle or technical challenge in their way. As an AI‑first company you will be encouraged to use AI tools to support your work, accelerate learning, and succeed in your role.

How You’ll Make an Impact

• Design and build backend systems that support scaling our AI solutions for 200K+ customers.
• Develop robust, reliable and scalable services to serve AI models in production environments.
• Contribute to evolving our agentic architecture, making our AI agents more self‑sufficient and performant.
• Contribute to a culture of ownership, experimentation, and customer‑centric product thinking.
• Engage with internal stakeholders to understand their needs and resolve blockers.
• Stay abreast of emerging AI trends and technologies, identifying and leveraging opportunities for their application within Klaviyo’s ecosystem.
• Work with the team on project planning and defining achievements, identifying dependencies, and meeting business goals.

What We’re Looking For

Pursuing an advanced degree in Computer Science, Artificial Intelligence, Machine Learning, or a related field, Graduating in December 2026 or May/June 2027

• Previous internship experience in AI, machine learning, or related fields, with a strong interest in building and deploying AI projects.
• Have hands‑on experience building and deploying generative AI and agentic AI applications into production.
• Demonstrate practical experience with key components of agentic architectures, including orchestration, evaluation, retrieval‑augmented generation (RAG), and safety guardrails.
• Proficient in Python and modern backend frameworks (FastAPI, Django preferred).
• Experience creating human and automated evals to ensure high AI model quality.
• Able to thrive in a fast‑moving, startup‑like environment.

Nice to Have

• Trained ML models in the past and deployed them in production systems to generate impact to businesses
• Experience in reinforcement learning
• Experience with large‑scale data processing tools including Spark.
• Experience building large scale backend systems

We use Covey as part of our hiring and / or promotional process. For jobs or candidates in NYC, certain features may qualify it as an AEDT. As part of the evaluation process we provide Covey with job requirements and candidate submitted applications. We began using Covey Scout for Inbound on April 3, 2025.

Please see the independent bias audit report covering our use of Covey here.

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.

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.

Base Pay Range For US Locations: $104,000 — $156,000 USD

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.

Klaviyo is committed to a policy of equal opportunity and non‑discrimination. 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, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law.

IMPORTANT NOTICE: Our company takes the security and privacy of job applicants very seriously. We will never ask for payment, bank details, or personal financial information as part of the application process. All our legitimate job postings can be found on our official career site. Please be cautious of job offers that come from non‑company email addresses (@klaviyo.com), instant messaging platforms, or unsolicited calls.

You can find our Job Applicant Privacy Notice here.