Principal Engineer – Partner Platform, APIs & Ecosystem Services

About Quizlet

Let’s Build the Future of Learning

Quizlet’s 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.

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

We’re hiring a Principal Engineer to lead the technical design of Quizlet’s extensible learning ecosystem, including our Partner API platform, Connector services, and Learn

OS plugin architecture. This is a pivotal role shaping Quizlet’s AI-powered integration layer for both human and agentic users.

You’ll define and implement the secure, scalable infrastructure that enables seamless learning experiences on and off Quizlet, from LMS integrations and productivity tools to AI agents and autonomous workflows.

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.

• API & Partner Platform Architecture:
  Own and evolve the external API gateway, SDKs, and developer tooling.
• Connector Runtime & Learn
  
  OS:
  Design sandboxed plugin runtimes to support real-time learning triggers across platforms like Discord, Google Calendar, Grammarly.
• Model Context Protocol (MCP) Interoperability:
  Architect Quizlet’s participation in agent-driven ecosystems, to integrate into AI services, like ChatGPT, Comet, Chrome.
• Agentic Enablement:
  Define APIs that allow external agents to create study sets, track progress, or initiate learning actions programmatically.
• Secure Developer
  
  Experience:
  
  Collaborate with Legal and T&S to implement audit, rate limiting, and permissions for third-party integrations.
• Data Exchange & Event Streams:
  Design publish-subscribe infrastructure for syncing learning activity across systems.

• 10+ years of engineering experience with large-scale, multi-tenant API or developer platforms.
• Strong track record designing extensible, secure APIs, SDKs, and plugin systems.
• Deep understanding of agent frameworks like MCP, protocol design, and AI/LLM interoperability.
• Significant experience building platform abstractions and developer enablement layers.
• Hands-on expertise with containerized services, OAuth 2.0, gRPC/REST, and event-driven systems.
• Passion for building platforms that enable scale, intelligence, and trust.
• Fluency with platform security, privacy, and system design.
• Proven ability to lead architectural transformation while shipping continuously.

• Quizlet is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. Salary transparency helps to mitigate unfair hiring practices when it comes to discrimination and pay gaps. Total compensation for this role is market competitive, including a starting base salary of $276,000 - $323,000, depending on location and experience, as well as company stock options.
• Collaborate with your manager and team to create a healthy work-life balance.
• 20 vacation days that we expect you to take.
• Competitive health, dental, and vision insurance (100% employee and 75% dependent PPO, Dental, VSP Choice).
• Employer-sponsored 401k plan with company match.
• Access to Linked In Learning and other resources to support professional growth.
• Paid Family Leave, FSA, HSA, Commuter benefits, and Wellness benefits.
• 40 hours of annual paid time off to participate in volunteer programs…