From ChatGPT:
CBL-Mariner is a Linux distribution developed by Microsoft. It is designed for use in cloud and edge computing environments, and is optimized for containerized workloads. The distribution includes a minimal set of components, which allows it to be more lightweight and efficient than some other Linux distributions.
CBL-Mariner is open source, and its components are available on GitHub. The distribution includes a set of tools and packages for building, deploying, and managing containerized applications, as well as tools for managing the underlying infrastructure.
CBL-Mariner is designed to be flexible and customizable, and it includes support for a wide range of hardware architectures and cloud environments. It can be used as a standalone operating system or as part of a larger software stack, depending on the needs of the organization.