Claude Code

Claude Code — Leaked Source (2026-03-31)
On March 31, 2026, the full source code of Anthropic's Claude Code CLI was leaked via a .map file exposed in their npm registry.

How It Leaked

Chaofan Shou (@Fried_rice) discovered the leak and posted it publicly:
"Claude code source code has been leaked via a map file in their npm registry!"
— @Fried_rice, March 31, 2026

The source map file in the published npm package contained a reference to the full, unobfuscated TypeScript source, which was downloadable as a zip archive from Anthropic's R2 storage bucket.

Overview

Claude Code is Anthropic's official CLI tool that lets you interact with Claude directly from the terminal to perform software engineering tasks — editing files, running commands, searching codebases, managing git workflows, and more.

This repository contains the leaked src/ directory.

- Leaked on: 2026-03-31
- Language: TypeScript
- Runtime: Bun
- Terminal UI: React + Ink (React for CLI)
- Scale: ~1,900 files, 512,000+ lines of code

Directory Structure

Core Architecture

1. Tool System (src/tools/)

Every tool Claude Code can invoke is implemented as a self-contained module. Each tool defines its input schema, permission model, and execution logic.

2. Command System (src/commands/)

User-facing slash commands invoked with / prefix.

3. Service Layer (src/services/)

4. Bridge System (src/bridge/)

A bidirectional communication layer connecting IDE extensions (VS Code, JetBrains) with the Claude Code CLI.

- bridgeMain.ts — Bridge main loop
- bridgeMessaging.ts — Message protocol
- bridgePermissionCallbacks.ts — Permission callbacks
- replBridge.ts — REPL session bridge
- jwtUtils.ts — JWT-based authentication
- sessionRunner.ts — Session execution management

5. Permission System…