A Plumber’s Guide to Git: Conclusion

• Part of A Plumber’s Guide to Git
• Last updated 13 March 2018

Well done for getting this far!

Let’s recap what we’ve learnt throughout the workshop:

• Git stores the contents of files as objects called blobs

• Git stores snapshots of the filesystem hierarchy in objects called trees, which point to blobs (individual files) and other trees (subdirectories)

• To build a sequential history and give context to snapshots, Git has objects called commits, which point to trees (the files and directories) and other commits (to build a history)

• Branches and refs are human-readable labels to specific commits

Here’s a whiteboard sketch that shows how it all fits together:

Along the way, you’ve learnt the plumbing operations that manipulate these objects and pointers. This is everything that happens in a typical Git workflow:

• git add is a combination of hash-object and update-index.
• git commit comes from write-tree, commit-tree, and if you’re on a branch, update-ref
• git checkout uses update-ref or symbolic-ref

I hope you now have a better understanding of How Git works under the hood, and it makes you a more confident and effective user when you return to the world of porcelain.

If you have any comments or feedback, please get in touch. I’d love to make the workshop even better for future readers.

Thanks for following along!