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zet-old/source/_zets/21.md

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+---
+title: Extracting a custom module with a Git subtree
+date: 2024-09-04 20:12:00
+tags: [Git]
+---
+
+To extract a directory from a repository and keep the history, you can use the `git subtree split` command to create a new branch:
+
+```shell
+git subtree split --prefix=web/modules/custom/my_module --branch=split
+Created branch 'split'
+17835f24069061326e9e065f076afd67434e1b2f
+```
+
+This will create a new branch with just the contents of the given directory.
+
+This can be pushed to a different repository:
+
+```shell
+git push git@github.com:opdavies/new-repo.git split:main
+```