Senior AI Research Engineer — Multimodal ML for Learning Apps

Duolingo; Pittsburgh (Allegheny County); On-site; USD 197,200 - 266,800; Full time

Job summary

Duolingo is seeking a Senior AI Research Engineer to join the Video Call team, advancing AI systems that support the core learning mission. You will work across LLMs, speech and text-to-speech domains, training and fine-tuning models, and collaborating with frontend, backend, and AI engineers to deliver scalable solutions.

The role expects leadership, strong communication, and a proven track record in applied ML, with responsibilities spanning model development, deployment, monitoring, and

Qualifications

• Proven experience as an AI research engineer, for example, in LLMs, multimodal modeling, speech, or related fields.
• Strong background in training and fine-tuning large models in an applied setting.
• Advanced degree in Computer Science, Engineering, or a related field with a focus on machine learning or artificial intelligence, or equivalent experience.
• Excellent leadership and communication skills, with the ability to lead and inspire a team.
• Technical depth sufficient to guide architecture and implementation trade-offs, evolve quality standards, and mentor engineers on best practices.
• Deep understanding of machine learning concepts, frameworks, and best practices.

Responsibilities

• Join a full-stack team of frontend, backend and other AI Research engineers, fostering a collaborative and innovative work environment.
• Contribute to the development and training of a variety of machine learning models, including large-scale neural networks, speech recognition, and text-to-speech systems.
• Collaborate with cross-functional teams to understand their needs, to align the models’ outputs with company objectives.
• Participate in and influence strategic product and business decision making with members of the Language Learning leadership group.
• Stay up-to-date with the latest developments in machine learning 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.

Skills

LLMs

Multimodal modeling

Speech processing

Education

Advanced degree in CS/Engineering/ML

Tools

TensorFlow

PyTorch

Job description

Duolingo is seeking a Senior AI Research Engineer to join the Video Call team, advancing AI systems that support the core learning mission. You will work across LLMs, speech and text-to-speech domains, training and fine-tuning models, and collaborating with frontend, backend, and AI engineers to deliver scalable solutions.

The role expects leadership, strong communication, and a proven track record in applied ML, with responsibilities spanning model development, deployment, monitoring, and