Research Engineer, Multimodal

About the role and team

As a Research Engineer on our Multimodal team, you’ll be a self-motivated, resourceful contributor with full-stack machine learning expertise—from data collection and training state-of-the-art models to building evaluations, optimizing inference algorithms, and refining systems based on user feedback.

In this role, you'll take end-to-end ownership of developing new multimodal capabilities, requiring you to think holistically about every stage of the ML pipeline. You'll need to be comfortable working across the full stack, tackling challenges at any level—from designing data pipelines to fine-tuning models and deploying real-time inference. If you thrive in an environment where you can wear multiple hats and solve complex problems with a hands-on approach, we’d love to hear from you.

What you'll do

• Determine the type of training data we need, finding where we can collect it, and writing distributed data gathering pipelines to ingest data.

• Develop new model architectures that push the state-of-the-art in terms of quality, scale, and inference speed.

• Create new evaluations that capture different aspects of generative outputs

• Write fast inference algorithms to serve these models at scale.

• Work with product teams to integrate feedback mechanisms into the product, which we use to improve the model.

• Work with large scale image/audio datasets.

Who you are

• "All Industry Levels": at least PhD (or equivalent) research experience.

• Experiences in diffusion modeling, large scale image/video data processing, and transformer model training.

• Strong engineering skills in deep learning frameworks of PyTorch.

• Track record of releases, publications, and/or open source projects relating to image / video generation, diffusion modeling, transformers, and so on.

• Have a deep understanding of the “whole stack” and track record of successfully owning projects from start to finish when it comes to designing, training, evaluating and deploying machine learning models, especially large language models.

About Character.AI

Character.AI empowers people to connect, learn and tell stories through interactive entertainment. Over 20 million people visit Character.AI every month, using our technology to supercharge their creativity and imagination. Our platform lets users engage with tens of millions of characters, enjoy unlimited conversations, and embark on infinite adventures.

In just two years, we achieved unicorn status and were honored as Google Play's AI App of the Year—a testament to our innovative technology and visionary approach.

Join us and be a part of establishing this new entertainment paradigm while shaping the future of Consumer AI!

At Character, we value diversity and welcome applicants from all backgrounds. As an equal opportunity employer, we firmly uphold a non-discrimination policy based on race, religion, national origin, gender, sexual orientation, age, veteran status, or disability. Your unique perspectives are vital to our success.

Compensation Range: $225K - $400K