Meet Legit SDK

Legit SDK is a Git-backed filesystem API that lets you build versioned, fail-safe applications with automatic commit history—no Git knowledge required.

🧪 Legit SDK Alpha Docs
We’d love your feedback as we refine the SDK — join the discussion on Discord .

How Legit Works with the Filesystem API

Everything is based on the filesystem API. If you know how to read and write files, you already know how to use Legit SDK.

The core operations are simple:

Read files - readFile() to access current or historical versions
Write files - writeFile() to create or update files (automatically creates commits)
Create directories - mkdir() to set up branches and organize files

That’s it. No special Git commands, no complex APIs. Just the filesystem operations you already know.


// Read a file
const content = await legitFs.promises.readFile('/.legit/branches/main/document.txt', 'utf8')
 
// Write a file (automatically creates a commit)
await legitFs.promises.writeFile('/.legit/branches/main/document.txt', 'Hello World', 'utf8')
 
// Create a directory (e.g., a new branch)
await legitFs.promises.mkdir('/.legit/branches/feature-xyz')

New to filesystem APIs? The concepts are universal—if you’ve worked with files in any language, you’ll feel at home. The filesystem API is the same interface you learned in your first programming courses.

Need a refresher on working with files? Check out W3Schools: Node.js File System or similar beginner resources to get started.

Why Legit SDK?

Legit SDK is built around three core ideas: fail-safe by design, effortlessly simple to use, and 100% Git compatible.

Fail-safe means giving your users the same superpowers you know from Git:

Roll back to any previous state
Branch off to run experiments with AI safely
Merge changes back when you’re happy with the result

Runs everywhere. Use Legit SDK as an API in the browser, Node.js, or mount it as a folder on your machine. That means instant compatibility with the stack of your choice — Python, Java, Node.js… you name it — from day one.

100% Git compatible. Legit SDK creates standard Git repositories under the hood. That means the entire Git ecosystem works with your Legit projects from day one.
GitHub, GitLab, CI/CD pipelines, Git GUIs, and all your existing Git tools. You can even open a Legit repository with standard Git commands if you need to. No lock-in, no proprietary formats—just Git.

Next Steps

Learn More

Explore the concepts and ideas behind Legit SDK: