Learn the Claude Code source code by building, not reading.
Progressive, challenge-driven, hands-on mastery.
5 levels, 8 weeks, from beginner to Claude Code Master
Boot flow, request lifecycle, codebase navigation
Command system, system prompt assembly, input processing
Tool anatomy, MCP protocol, tool execution engine
Sub-agents, coordinator mode, plan & worktree
Hooks, permissions, compaction & cost tracking
┌─────────────────────────────────────────────────────────────┐
│ main.tsx (Entry) │
│ Boot → Config → Migrations → Setup → REPL │
└──────────────────────┬──────────────────────────────────────┘
│
┌──────────────┴──────────────┐
│ setup.ts │ ← Level 1
│ CWD → Hooks → Worktree │
└──────────────┬──────────────┘
│
┌──────────────┴──────────────┐
│ QueryEngine.ts │ ← Level 2
│ System Prompt → Messages │
└──────────────┬──────────────┘
│
┌──────────────┴──────────────┐
│ query.ts │ ← Level 3
│ Compaction → API Stream │
│ Tool Extraction → Execute │
└──────────────┬──────────────┘
│
┌──────────────┴──────────────┐
│ AgentTool / Coordinator │ ← Level 4
│ Sub-agents → Worktrees │
└──────────────┬──────────────┘
│
┌──────────────┴──────────────┐
│ Hooks / Permissions / Cost │ ← Level 5
│ Production-grade systems │
└─────────────────────────────┘Earn XP through exercises, challenges, and boss battles