Principal Engineer, Personalization & Recommendation

Job Description

Job Description

About Quizlet :

At Quizlet, our mission is to help every learner achieve their outcomes in the most effective and delightful way. Our $1B+ learning platform serves tens of millions of students every month,  including two-thirds of U.S. high schoolers and half of U.S. college students, powering over 2 billion learning interactions monthly.

We blend cognitive science with machine learning to personalize and enhance the learning experience for students, professionals, and lifelong learners alike. We’re energized by the potential to power more learners through multiple approaches and various tools.

Let’s Build the Future of Learning

Join us to design and deliver AI-powered learning tools that scale across the world and unlock human potential.

About the Team :

The Applied AI team's mission is to invent and deploy the next generation of intelligent, personalized, and adaptive learning experiences that will define the future of Quizlet. This team represents a major investment and consolidation of our AI efforts, created to move from siloed features to a unified and powerful product portfolio. We are accountable for driving the majority of Quizlet's business growth and building a product that is recognized externally as best-in-class.

About the Role :

As the Principal Engineer for Personalization & Recommendation Systems, you will serve as the technical authority and visionary for building a deep, holistic understanding of our learners. You will tackle our most complex technical challenges, architecting the core intelligence of our product to transform Quizlet from a memorization tool into a personalized, AI-powered coach that drives user engagement, retention, and monetization.

Additionally, you’ll be the technical lead for a team of talented engineers, guiding the architecture and execution of recommendation and matching systems that connect students to the most relevant content across our entire platform. This includes : search, ads, and our content feed. Your technical leadership will be pivotal in shaping the future of AI at Quizlet.

We’re happy to share that this is an onsite position in our San Francisco office. To help foster team collaboration, we require that employees be in the office a minimum of three days per week : Monday, Wednesday, and Thursday and as needed by your manager or the company. We believe that this working environment facilitates increased work efficiency, team partnership, and supports growth as an employee and organization.

In this role, you will :

• Architect, design, and execute the technical roadmap for all personalization and recommendation initiatives, directly contributing to Quizlet’s key business metrics like Engaged Learners, Subscriber Conversion, and Revenue Growth
• Set the technical direction and provide mentorship to a high-performing team of 10+ machine learning and software engineers, fostering a culture of innovation and high-impact execution
• Spearhead the technical development of "User 360" - a comprehensive understanding of our learners derived from synthesizing behavioral signals, explicit inputs, and conversation history into rich user profiles and embeddings
• Own the end-to-end technical lifecycle of machine learning models that power all matching and ranking systems across the product (ads, search, feed), optimizing for both offline performance (e.g., NDCG) and online business impact (e.g., CTR, user satisfaction)
• Drive technical excellence in building scalable, reliable, and cutting-edge ML systems, tackling the most ambiguous and complex problems
• Partner closely with leaders in Product, Data Science, and the AI & Data Platform teams to deliver on a shared vision of an AI-driven learning experience
• Influence the technical direction of the broader engineering organization by establishing best practices and mentoring senior engineers

What you bring to the table :

Bonus points if you have :

Compensation, Benefits & Perks :

Why Join Quizlet?

\uD83C\uDF0E Massive reach : 60M+ users, 1B+ interactions per week

\uD83E\uDDE0 Cutting-edge tech : Generative AI, adaptive learning, cognitive science

\uD83D\uDCC8 Strong momentum : Top-tier investors, sustainable business, real traction

\uD83C\uDFAF Mission-first : Work that makes a difference in people’s lives

\uD83E\uDD1D Inclusive culture : Committed to equity, diversity, and belonging

We strive to make everyone feel comfortable and welcome!

We work to create a holistic interview process, where both Quizlet and candidates have an opportunity to view what it would be like to work together, in exploring a mutually beneficial partnership.

We provide a transparent setting that gives a comprehensive view of who we are!

In Closing :

At Quizlet, we’re excited about passionate people joining our team—even if you don’t check every box on the requirements list. We value unique perspectives and believe everyone has something meaningful to contribute. Our culture is all about taking initiative, learning through challenges, and striving for high-quality work while staying curious and open to new ideas. We believe in honest, respectful communication, thoughtful collaboration, and creating a supportive space where everyone can grow and succeed together.”

Quizlet’s success as an online learning community depends on a strong commitment to diversity, equity, and inclusion.

As an equal opportunity employer and a tech company committed to societal change, we welcome applicants from all backgrounds. Women, people of color, members of the LGBTQ+ community, individuals with disabilities, and veterans are strongly encouraged to apply. Come join us!

To All Recruiters and Placement Agencies :

At this time, Quizlet does not accept unsolicited agency resumes and / or profiles.

Please do not forward unsolicited agency resumes to our website or to any Quizlet employee. Quizlet will not pay fees to any third-party agency or firm nor will it be responsible for any agency fees associated with unsolicited resumes. All unsolicited resumes received will be considered the property of Quizlet.

We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.