Keras

Keras is an open-source deep learning API that simplifies building and training neural networks with minimal, readable code, maintained as part of the Google-backed TensorFlow ecosystem with community contributions. It works across JAX, TensorFlow, and PyTorch backends, letting the same model code move between frameworks, and offers multiple ways to build models including a Functional API, a Subclassing API for custom layers, and Sequential patterns. KerasHub provides a library of pre-trained models including Gemma, Llama, Stable Diffusion, and Mistral, and Keras includes built-in training tools for easy model compilation, training via model.fit(), and evaluation. It is used by major organizations including Google, YouTube, Waymo, NASA, CERN, Netflix, Spotify, Amazon, and Uber for research and production systems, and is completely free and open source, hosted on GitHub.