Principal Machine Learning Engineer

About the Team

At Stitch Fix, we are at the forefront of innovation, creating cutting-edge solutions that blend fashion, technology, and data science. Our data science team combines machine learning with expert human judgment to generate innovative recommendations and insights that transform the way our clients discover what they love. We believe in a curiosity-driven data science culture where members are empowered to deliver impact through end-to-end model development. The diversity of the problems that we work on and the data-rich environment of our business make it possible, even essential, to bring the tools of multiple disciplines to bear on our hardest problems.

The Foundational Models team focuses on developing the core recommender system, which not only personalizes the client experience but also informs merchandising strategies. The team’s goal is to enhance business outcomes by improving model performance while ensuring optimal latency, uptime, and cost efficiency.

About the Role

In this role, you will be building the next generation ML systems that transform the way people find what they love. As a Machine Learning Engineer, your focus will be on building, productionizing and scaling of machine learning models, and promoting engineering excellence.

You will get the opportunity to work with data scientists, as well as lead work cross-functionally with Strategy, Product, Merchandising, Marketing, and Engineering partners to build and enhance those capabilities.

You're excited about this opportunity because you will…

• Bring your engineering excellence to improve how we serve real time recommendations in production at scale. 
• Make a substantial impact on personalization across multiple dimensions by creating the infrastructure that allows us to build the next generation of recommendation systems.
• Collaborate with data scientists on a variety of sophisticated machine learning algorithms.
• Work closely with partners in ML Platform Eng, Engineering, Product and Merchandising teams.
• Be empowered to take initiative and follow your innate curiosity.

We’re excited about you because…

• You have 5+ years of experience in building high-throughput, resilient backend systems, with demonstrated expertise in deploying and maintaining machine learning models in production.
• You have 5+ years of advanced python development experience, including familiarity with data manipulation using spark and SQL.
• You have a solid foundation in machine learning, plus a bonus of evaluating recommender systems.
• You are familiar with modern ML frameworks (e.g. PyTorch, TensorFlow) and model deployment frameworks leveraging container orchestration.
• You have hands-on experience with observability tools (e.g., Datadog, Prometheus) and a deep understanding of how to measure and optimize system latency.
• You excel at translating complex technical concepts into clear, actionable insights for cross-functional partners, including Product, Design, and Engineering, to build consensus and drive projects forward.
• You are driven by a deep curiosity to explore new technologies and take calculated risks, with a focus on identifying and implementing best practices that elevate the team's engineering standards.

Why you'll love working at Stitch Fix...

• We are a group of bright, kind people who are motivated by challenge. We value integrity, innovation and trust. You’ll bring these characteristics to life in everything you do at Stitch Fix.
• We cultivate a community of diverse perspectives— all voices are heard and valued.
• We are an innovative company and leverage our strengths in fashion and tech to disrupt the future of retail. 
• We win as a team, commit to our work, and celebrate grit together because we value strong relationships.
• We boldly create the future while keeping equity and sustainability at the center of all that we do. 
• We are the owners of our work and are energized by solving problems through a growth mindset lens. We think broadly and creatively through every situation to create meaningful impact.
• We offer comprehensive compensation packages and inclusive health and wellness benefits.