As a Senior Research Engineer at Fitbit (a Google company), you'll contribute to the development of cutting-edge AI/ML solutions for their health and fitness products. Responsibilities include designing, implementing, and testing machine learning models, collaborating with stakeholders, contributing to documentation, and troubleshooting system issues. You'll work with frameworks like TensorFlow, PyTorch, or Jax, focusing on model pretraining, fine-tuning, evaluation, and optimization. The role requires experience in software development, testing, and design, along with a strong understanding of data structures and algorithms. The ideal candidate will have a Master's or PhD in a relevant field and experience publishing research in machine learning journals.