Snapcraft, the package management system designed to streamline software delivery across Linux distributions, leverages the concept of Snaps, which encapsulate and isolate entire applications for enhanced security, stability, and portability. This system allows a single Snap to be installed on various Linux versions such as Ubuntu, Debian, and Fedora, using cross-distro tools aimed at simplifying the process of building and publishing software. The document outlines the process of building Snap packages using CircleCI 2.0, emphasizing the use of machine and Docker executors to manage dependencies across different Linux versions. It discusses testing strategies for Snap packages, including running acceptance tests on multiple Linux distributions using CircleCI Workflows to ensure compatibility and functionality before publishing to the Snap Store. The text also covers methods for persisting Snap packages and securely handling Snap Store credentials during the deployment process.