This repository implements the Ghost CLI, a command-line tool for installing, configuring, updating, and managing Ghost CMS instances on Linux servers (Ubuntu). The system is a monolithic Node.js application with a plugin architecture. Its core responsibilities include: (1) resolving and downloading Ghost versions from the npm registry, (2) setting up required infrastructure (MySQL, nginx, systemd), (3) managing instance lifecycle (start/stop/restart), (4) handling content migration and import/export via the Ghost Admin API, (5) running health checks via the doctor command, and (6) handling major version upgrades with rollback support. Architecturally, the CLI is composed of a Command base class with yargs integration, a layered task system using listr2 for sequential/parallel operations, and an extension system that allows built-in plugins (nginx, systemd, MySQL) to inject commands, setup steps, doctor checks, and custom process managers. Configuration is managed via JSON files, and dependencies are installed using either yarn or pnpm. The codebase is well-structured with clear separation of concerns: commands in lib/commands/, tasks in lib/tasks/, utilities in lib/utils/, and extensions in extensions/. The tool depends on external services: npm registry for version resolution, Ghost Admin API for import/export, system tools (nginx, systemd, MySQL) for production setups, and acme.sh for SSL certificate management. It supports local development (direct node process) and production (systemd service). The codebase is actively maintained, with support for Ghost versions 1.x through 6.x, Node.js 22/24, and MySQL 5.6 through 9.4. While there is some legacy code for older Ghost versions, the overall architecture is modern, testable, and modular.