Claude Reviews ClaudeWhen AI Reads Its Own Source Code

17 architecture deep dives written by Claude, dissecting Claude Code v2.1.88 — 1,902 files, 477K lines of TypeScript.

Query Engine

The 12-step state machine that powers the core while(true) tool loop — the "brain" of Claude Code.

42+ tools as self-contained modules — Schema-driven registration, validation, and execution.

7-layer defense-in-depth — from config rules to AST analysis to OS sandboxing.

Multi-agent coordination — mailbox IPC, backend detection, and permission delegation.

3-layer context assembly — system prompts, CLAUDE.md memory, per-turn attachments.

Forked Ink + React 19, Vim mode, IDE bridge — 140+ components powering the CLI experience.