Staff AI Research Engineer

Our mission at Duolingo is to develop the best education in the world and make it universally available. It’s a big mission, and that’s where you come in!

At Duolingo, you’ll join a team that cares about finding innovative solutions to complex technical problems , running countless experiments (300+ at a time!) with our massive user base to make data-driven decisions, and educating our users and employees alike. You’ll have limitless learning opportunities, mentorship and collaboration with world-class minds, and a variety of projects with large scopes — while doing work that’s both fun and meaningful.

Join our life-changing mission to develop education for our half a billion (and growing!) learners around the world.

About the role

We are looking for an experienced AI Research Engineer to join our Duolingo English Test security team. The ideal candidate will have a proven track record as an AI research engineer, with extensive experience in developing, training, and fine-tuning large neural networks. On the security team, we're building AI systems to help detect fraudulent testing behavior. These state-of-the-art systems range from biometric signals like keystroke signatures to vision and sound models to gaze tracking or language models to detect whether a test-taker used an LLM to generate their answer. Given the broad set of AI domains, broad experience in AI/ML is highly desirable.

You will...

• Join a team of backend and AI Research engineers, fostering a collaborative and innovative work environment.


• Contribute to the development and fine-tuning of large-scale neural network models, with a focus on agentic AI.


• Collaborate with cross-functional teams to understand their needs, to align the agentic models outputs with company objectives.


• Stay up-to-date with the latest developments in machine learning, particularly in LLMs and agents, and apply this knowledge to drive advancements in our projects.


• Mentor team members, providing guidance and support in their professional development.


• Ensure the delivery of high-quality, scalable, and efficient machine learning solutions.

You have...

• Proven experience as an AI research engineer, for example, in LLMs, computer vision or related fields.


• Strong background in training and fine-tuning large neural networks.


• Advanced degree in Computer Science, Engineering, or a related field with a focus on machine learning or artificial intelligence.


• Excellent leadership and communication skills, with the ability to manage and inspire a team.


• Deep understanding of machine learning concepts, frameworks, and best practices.

We post a multi-level salary range for all of our roles.

This is not inclusive of the rest of our awesome portfolio that includes equity compensation and world-class benefits. Our salary ranges are the same for all US locations. Your recruiter can share more details about the range for a specific level during the hiring process. The actual salary within the range is determined by many factors including but not limited to, skills, experience, education, and internal equity.

Salary Range:

$213,600—$384,000 USD

Take a peek at how we care for our employees' holistic well-being with our benefits here .

We will do everything we can within reason to make sure that your interview takes place in an environment that fairly and accurately assesses your skills. If you need assistance or accommodation, please contact [email protected] .

Duolingo is proud to be an Equal Employment Opportunity employer. We do not discriminate based upon race, religion, color, national origin, gender (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, or other applicable legally protected characteristics.

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