Git Subtree
Git Subtree is a Git command-line tool that enables developers to manage project dependencies by embedding external repositories as subdirectories within a main repository, while preserving the full commit history. It allows for bidirectional synchronization between the main repository and the embedded subtree, making it useful for code sharing and modular development. Unlike Git Submodules, subtrees are stored as regular files in the repository, simplifying workflows for many teams.
Developers should use Git Subtree when they need to include external code (like libraries or shared components) directly within their project's repository without the complexity of submodules, especially in scenarios where the external code needs to be modified and synced back. It's ideal for projects that require a monolithic repository structure but still want to manage dependencies cleanly, such as in large-scale applications or when deploying code that must include all dependencies in one place.