Have you ever wondered how Git actually works under the hood? What really happens when you run `git init`? 🤔 I built a Git clone in Go from scratch to understand how Git actually works. Trunk is a functional Git core written in Go that directly reads and writes the .git directory instead of shelling out to Git. While building it, I dug into Git’s internals and learned how its object model, refs, and plumbing commands really operate under the hood. Here's what I discovered: Key Learnings: 1️⃣ Git is a Content-Addressable Storage System Git isn't a "diff engine" - it's essentially a key-value database where every piece of content gets a unique SHA-1 hash as its key. 2️⃣ Commits are Full Snapshots, Not Diffs Contrary to popular belief, each commit stores the ENTIRE state of your project. Git optimizes this through compression and deduplication - identical files across commits share the same storage. 3️⃣ The Merkle Tree Architecture Git uses a Merkle tree structure where: - Blobs store file content (no filenames!) - Trees represent directories (mapping names to hashes) - Commits link trees with metadata - Any change propagates up: file → tree → root tree → commit 4️⃣ Clever Object Storage Objects are stored in `.git/objects/` using a smart scheme: - First 2 characters of the hash = directory name - Remaining 38 characters = filename - All compressed with zlib 5️⃣ Branches Are Just Pointers A branch is simply a lightweight pointer to a commit hash. That's why creating branches is so cheap! 💻 The Implementation: I built both plumbing (low-level) and porcelain (high-level) commands: - Plumbing: hash-object, cat-file, update-index, write-tree, commit-tree - Porcelain: commit, log The project is compatible with standard Git repositories, reinforcing the idea that Git is fundamentally clever file organization plus cryptographic hashing. Check out the full implementation on GitHub: https://lnkd.in/g6AG2js5 #Git #SoftwareEngineering #OpenSource #VersionControl #Golang #DevOps #Programming #TechEducation #ComputerScience

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