Curated source guide

ReactOS source explorer

Explore the ReactOS source code interactively. Study its NT kernel architecture, Win32 subsystem, driver model, boot flow, and Windows compatibility layers.

Guide chapters

1. Chapter 1 — The Tree and the Build Are the First Abstractions
2. Chapter 2 — Kernel, HAL, and Boot Flow
3. Chapter 3 — User Mode, Win32, and Shared DLLs
4. Chapter 4 — Drivers and Hardware Support
5. Chapter 5 — How to Read ReactOS Effectively

Key directories

• ntoskrnl/ — NT kernel core, system services, memory, object manager, and executive code
• hal/ — Hardware abstraction layer and platform-specific low-level code
• boot/ — Boot loader and early startup support
• dll/ — Shared system DLLs, Win32 APIs, and compatibility surfaces
• base/ — Base system code and shared runtime pieces
• modules/ — Application and subsystem modules that compose the OS image