ruvector/docs/research/claude-code-rvsource/14-source-extraction.md

14 - Source Extraction and Code Metrics

Binary Analysis

Distribution Formats

Claude Code ships in two forms:

Format	Path	Size	Version
Bun SEA (ELF)	~/.local/share/claude/versions/2.1.90	229,902,976 bytes (219 MB)	2.1.90
NPM bundle	@anthropic-ai/claude-code/cli.js	11,044,554 bytes (10.5 MB)	2.0.62

The Bun SEA binary is a dynamically linked ELF executable embedding the Bun runtime (v1.2+) with the JavaScript bundle inlined. The NPM package contains the same logical code as a single minified cli.js file plus tree-sitter WASM modules and a vendored ripgrep binary.

Binary Structure (Bun SEA)

ELF 64-bit LSB executable, x86-64
├── Bun runtime (~219 MB)
│   ├── V8/JavaScriptCore bindings
│   ├── libc, libcrypto, libssl
│   └── Node.js compatibility layer
├── Embedded JS bundle (~11 MB equivalent)
│   ├── Minified application code
│   ├── Bundled npm dependencies (lodash, zod, ink, etc.)
│   └── Tree-sitter grammars (WASM)
└── Bun SEA metadata markers
    ├── @bun @bytecode @bun-cjs
    └── {"method":"Bun.canReload"}

NPM Package Layout

@anthropic-ai/claude-code/
├── cli.js              11,044,554 bytes  (single minified bundle)
├── sdk-tools.d.ts          65,511 bytes  (TypeScript type defs for tools)
├── package.json             1,196 bytes
├── tree-sitter-bash.wasm 1,380,769 bytes
├── tree-sitter.wasm        205,498 bytes
├── vendor/
│   └── ripgrep/            (bundled rg binary)
├── LICENSE.md
└── README.md

Version Management

Multiple versions coexist under ~/.local/share/claude/versions/:

• 2.1.86 (228,280,960 bytes) - 2025-03-27
• 2.1.87 (228,280,960 bytes) - 2025-03-29
• 2.1.90 (229,902,976 bytes) - 2025-04-02 (current)

The active version is symlinked: ~/.local/bin/claude -> ~/.local/share/claude/versions/2.1.90

Code Metrics (from cli.js v2.0.62)

Metric	Count
File size	11,044,554 bytes
Lines (minified)	4,836
Estimated functions	19,464
Async functions	884
Arrow functions	23,537
Classes	1,557
Class inheritance (extends)	956
for await loops	41
yield* statements	18
Async generators	6 (core loop functions)
Node.js built-in imports	25+ modules

Estimated Original Source Size

The minified bundle is ~11 MB in 4,836 lines. Given typical minification ratios (3-5x for well-structured TypeScript), the original source is estimated at 33-55 MB / 50,000-150,000 lines across hundreds of modules.

Minification Characteristics

The code uses aggressive mangling:

• All local variables shortened to 1-3 characters (A, Q, B, G, Z, Y)
• Module-scoped functions use short hashes (s$, ye, nB, QA, wG)
• Class names are 2-4 character hashes (L6, V9, GI, RX, oJ, c90)
• Original names survive only in string literals and public API surfaces

Key Identifiable Functions (from code patterns)

Minified Name	Likely Original	Evidence
s$	agentLoop / queryLoop	Core async generator; receives messages, systemPrompt, canUseTool, toolUseContext
ye	resolveModel	Takes permissionMode, mainLoopModel, exceeds200kTokens
Ll	createInitialAppState	Returns full AppState object with all fields
QA	trackEvent / telemetry	Called everywhere with event name + payload
nB	updateSettings	Writes to settings store
wG	logDebug	Debug logging with event names like "query_query_start"
Y7	getMainLoopModel	Returns current model
Y0	getCwd	Returns current working directory
GB	getProjectDir	Returns project directory
Bd	getContextWindow	Takes model, returns context window size
xC	getToolPermissionContext	Returns permission context object
Sn	extractTextContent	Extracts text from API response
B0	getAgentId	Returns current agent ID

Extraction Methods

Method 1: NPM Package (recommended)

The cli.js from the NPM package is directly analyzable JavaScript:

CLI="$(npm root -g)/claude-flow/node_modules/@anthropic-ai/claude-code/cli.js"
# or install directly:
npm pack @anthropic-ai/claude-code && tar xzf anthropic-ai-claude-code-*.tgz

Method 2: Binary Strings

strings ~/.local/share/claude/versions/2.1.90 | grep -c 'function\|class '
# Returns ~9,887 readable JS fragments

The binary contains the same JS but embedded within the Bun SEA container. The NPM package provides cleaner access to the same code.

Method 3: Bun SEA Extraction

The Bun SEA format embeds a bytecode blob. To extract:

# Find the JS entry section
strings -t d binary | grep '#!/usr/bin/env' | head -1
# Use offset to extract the embedded module

Source Files Referenced

• Extracted module analysis: extracted/agent-loop.rvf
• Tool dispatch patterns: extracted/tool-dispatch.rvf
• Permission system: extracted/permission-system.rvf
• MCP client: extracted/mcp-client.rvf
• Context manager: extracted/context-manager.rvf
• Streaming handler: extracted/streaming-handler.rvf

Dependencies (Node.js Built-in Imports)

assert, async_hooks, child_process, crypto, events, fs, fs/promises,
http, https, module, net, os, path, process, stream, tty, url, util, zlib
node:buffer, node:child_process, node:crypto, node:fs, node:fs/promises,
node:http, node:https, node:module, node:net, node:os, node:path,
node:process, node:stream, node:timers/promises, node:tty, node:url,
node:util, node:zlib

Bundled Third-Party Libraries (identified from code patterns)

• Zod (schema validation - S.string(), S.enum(), S.record())
• Ink / React (terminal UI - createElement, useCallback, useEffect, useRef)
• Sentry (error tracking - globalEventProcessors, _dispatching)
• GrowthBook (feature flags - stickyBucketService, getExperiment)
• Statsig (experimentation - _getFeatureGateImpl)
• Sharp (image processing - @img/sharp-* optional deps)
• node-forge (crypto - aes.startEncrypting, aes.createDecryptionCipher)
• tree-sitter (AST parsing - WASM modules)
• ripgrep (file search - vendored binary)