Introduction to the 'git subtree' command. Covers adding a repository as a subtree and updating (reverting) that subtree to an older state. Subtrees are a way to track other git repos as dependencies of your own. They provide the same mechanism as Git Submodules but with a different approach.
See also:
Introduction to Git Submodules:
https://youtu.be/UQvXst5I41I
More about Git Submodules:
https://youtu.be/w4AyLtIEibo
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