Senior Software Engineer, Internal Experimentation Platform

Location: Boston, MA

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.