Senior Software Engineer, Internal Experimentation Platform

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. Want to learn more about life at Klaviyo? Visit careers.klaviyo.com to see how we empower creators to own their own destiny.

Location: Boston, MA

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. Want to learn more about life at Klaviyo? Visit careers.klaviyo.com to see how we empower creators to own their own destiny.

Klaviyo operates a real-time data analytics platform coded primarily in Python that is built for massive scale and hosted on Amazon Web Services (AWS). Engineers come to Klaviyo with experience in a variety of languages and from a number of disciplines. 

The Internal Experimentation team is responsible for building and maintaining our internal experimentation platform in Klaviyo. The platform supports experiment tracking, feature rollout, AB tests, multivariable tests and other forms of experimentation to enable rapid feature development and machine learning model iteration. The team works closely with internal stakeholders to gather requirements and design the systems needed to experiment with billions of data points. The team is full stack and we work with front-end, back-end and big data systems to build the necessary infrastructure required to ensure robust experimentation capabilities and data driven feature and algorithm development. 

We are looking for a senior software engineer to evaluate, design and build out the internal experimentation platform. You can expect to be deeply involved in the technical discussions on how we architect a novel system to support experimentation for our internal stakeholders in the Klaviyo application. You will have ownership of projects that contribute to the team's mission, goals, and roadmap. You will also closely collaborate with analysts, data scientists and data engineers to define best practices for experiments that are statistically rigorous. Your tech stack will include Python, Typescript, React, AWS, Kubernetes, Django, Pandas, NumPy and Spark. 

How You Will Make A Difference

• Deliver key product capabilities in the experimentation area to learn and optimize our capabilities that serve millions of customers per day.
• Design and implement systems in the internal experimentation framework to optimize Klaviyo features and data science models for 167k companies and 7 billion+ customer profiles. 
• Work with data volumes representing several orders of magnitude to deliver experiences that provide value to our smallest as well as largest customers
• Work cross functionally with product, design, data science and analytics teams
• Have ample opportunities for growth given the scope of this role and the team’s central role in Klaviyo’s product

Who You Are

• 5+ years experience working in a SaaS product in full stack capacity.
• You have an in-depth understanding of common web architectures when it comes to highly scalable systems.  
• Successfully delivered on complex projects spanning multiple quarters.
• Some experience with MLOps, Experimentation and statistical analysis.

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.

The pay range for this role is listed below. Some sales and success roles are also eligible for variable compensation and hourly non-exempt roles are eligible for overtime in accordance with applicable law. This role is eligible for benefits, including: medical, dental and vision coverage, health savings accounts, flexible spending accounts, 401(k), flexible paid time off and company-paid holidays and a culture of learning that includes a learning allowance and access to a professional coaching service for all employees.

Base Pay Range For US Locations:$152,000—$228,000 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.

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.

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