Git submodules are a powerful and helpful feature within Git's code management ecosystem. Git submodules integrate external Git repositories into a primary repository, serving various purposes. They are particularly valuable for dependency management, including external libraries or separate modules while maintaining version control independence. Submodules also prove helpful for code reuse, allowing shared codebases to be incorporated into multiple projects. They facilitate code modularity and isolation, particularly in larger projects where distinct teams or individuals handle different components.

Additionally, submodules aid in versioning, enabling specific versions for stability. Although they enhance maintainability by simplifying updates, it is essential to note that working with submodules introduces complexities, necessitating familiarity with their specific commands and workflows. 

Working with nested Git repositories adds layer of complexity within a main Git project. One of the issues that arises is how I commit and push changes to a submodule and then pick up those changes in my main project. This tutorial will demonstrate how to make changes to a git submodule, commit those changes, and then push those changes to the submodule Git repository. After that, we will pull those changes from our main project repository.

1. In the Git Submodule Directory

First, we need to navigate to the submodule to which we want to make changes, git add those changes, git commit, and finally, git push those changes to the submodule repo. Since git submodules are also git repositories with their own .git configurations, the process is quite straightforward.

Once this is done, we can change directories back to our project root.

2. In the Main Git Repo Directory

Second, we must navigate back to our main project, the Git repository that uses Git submodules as project dependencies. When we are at the root of our project, we can git add the submodule we just pushed changes for, git commit, and finally, git push.

Your entire project, including your Git submodules, should be updated!

Conclusion

This tutorial provided a clear and step-by-step approach on how to make changes to a submodule, commit those changes, push them to the submodule repository, and then integrate them into the main project without issues. Demonstrating the process in detail, the tutorial addressed a common challenge associated with working with nested Git repositories.

Using Git submodules offers developers various benefits, such as improved project organization, collaboration, and version control. Although Git submodules may have a steep learning curve, their advantages in terms of code isolation, maintainability, and collaboration make them a valuable asset in the Git toolkit.