AXLearn is a deep learning library built by Apple based on JAX and XLA. It takes an object-oriented approach to address software engineering challenges in large-scale deep learning model development. Its configuration system allows users to combine models from reusable building blocks and integrate with other libraries (such as Flax and Hugging Face transformers). AXLearn aims to scale training, supporting models with hundreds of billions of parameters efficiently trained on thousands of accelerators, suitable for deployment on public clouds. It also adopts a global computation paradigm, allowing users to describe computations on a global virtual machine instead of individual accelerators. AXLearn supports a wide range of applications, including natural language processing, computer vision, and speech recognition, and includes baseline configurations for training state-of-the-art models.