Container Tool Kit (CTK) is a web application that provides a visual editor for Docker Compose and Kubernetes manifest files. Users can create and manage projects by dragging and dropping services, volumes, and networks onto a canvas, editing node configurations through detailed forms, and viewing the resulting YAML/JSON in a synchronized code editor. The backend is built with FastAPI and PostgreSQL, handling project persistence, user authentication (JWT-based), manifest generation (including calling kompose for Kubernetes), and project import from remote YAML URLs. The frontend is a React/TypeScript single-page application using jsPlumb for the interactive canvas, Formik for form management, and Monaco Editor for code editing. The application supports both anonymous and authenticated usage, with features like autosave, visibility toggles, and pagination for project lists.