This repository is a comprehensive architectural analysis of the leaked Claude Code CLI source code, presented as 18 detailed markdown documents. It systematically dissects the entire 512K-line TypeScript codebase across all subsystems: startup pipeline, query engine with AsyncGenerator state machine, 39-tool system with 30+ method interfaces, three-layer Bash security (23 checks), ResolveOnce permission system with 6-way concurrent race handling, 150+ field immutable state management, multi-provider API service layer, dual-transport IDE Bridge integration, file-based memory system with Sonnet semantic recall, lazy-loaded plugin system, custom React reconciler with double-buffered terminal rendering, virtual scrolling with Float64Array offset tracking, 103-command system, build-time DCE with GrowthBook runtime gates, and 12 cross-cutting architectural patterns. While the repository does not contain the actual leaked source code, it serves as an exceptionally well-structured reference for understanding how a production-grade AI coding assistant is architected. The analysis includes code snippets, design rationale, architecture diagrams, and performance optimization details. The work is of publication quality, demonstrating deep software engineering expertise and systematic analytical methodology. Researchers and engineers studying AI-assisted programming tools, terminal UI frameworks, or industrial TypeScript architectures will find this a valuable reference.