Verz

A lightweight Git implementation in C++ supporting core version control operations — including cloning from GitHub, staging, committing, and branch management.

Commands

Command	Description
verz init	Initialize a new repository
verz register <user> <email>	Register author identity for commits
verz add <path>...	Stage files for the next commit
verz commit -m <message>	Commit staged changes
verz branch	List all branches
verz branch <name>	Create a new branch at HEAD
verz switch <name>	Switch to a branch (restores working tree)
verz delete-branch <name>	Delete a branch
verz clone <url> <dir>	Clone a remote GitHub/Git repository
verz cat-file -p <sha>	Print object contents
verz hash-object [-w] <file>	Hash a file as a blob object
verz ls-tree [-r|--name-only] <sha>	List tree object entries
verz write-tree	Write working directory as a tree object
verz commit-tree <tree> [-p <parent>] -m <msg>	Low-level commit creation

Requirements

• C++17 compatible compiler (g++, clang++)
• OpenSSL (libssl, libcrypto) — SHA1 hashing
• zlib (libz) — object compression
• libcurl (libcurl) — HTTP for verz clone

Installing Dependencies

Ubuntu/Debian:

sudo apt-get install build-essential libssl-dev zlib1g-dev libcurl4-openssl-dev

Fedora/RHEL:

sudo dnf install gcc-c++ openssl-devel zlib-devel libcurl-devel

Arch Linux:

sudo pacman -S base-devel openssl zlib curl

macOS:

brew install openssl zlib curl

Building

make          # default build
make debug    # with debug symbols (-g -O0)
make release  # with optimizations (-O3)
make clean    # remove build artifacts
make rebuild  # clean + build

Binary is at bin/verz.

Typical Workflow

# New repo
verz init
verz register Alice alice@example.com
echo "hello" > README.md
verz add .
verz commit -m "initial commit"

# Branching
verz branch feature
verz switch feature
echo "new feature" > feature.txt
verz add feature.txt
verz commit -m "add feature"
verz switch main

# Cloning
verz clone https://github.com/user/repo ./repo

Repository Structure (.verz/)

.verz/
├── HEAD              ← "ref: refs/heads/main"
├── index             ← staging area (plain text)
├── objects/          ← content-addressed object store
│   ├── ab/
│   │   └── cd1234…  ← zlib-compressed blob/tree/commit
│   └── …
├── refs/
│   └── heads/
│       ├── main      ← commit sha
│       └── feature   ← commit sha
└── user/
    └── config        ← "username\nemail\n"

Documentation

See docs/ for detailed internals of each command, including object formats, helper functions, and implementation notes.

• docs/internals.md — deep-dive into all binary/text formats: objects, index, HEAD/refs, packfile, VLI, delta, pkt-line.
• docs/verz-vs-git.md — contrast between verz and real Git: what's faithful, what's simplified, and why.

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For educational purposes — a from-scratch implementation of core Git internals in C++17.