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book/src/introduction.md

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+# Introduction
+
+> [!NOTE]
+> This book was written entirely by Claude Opus 4.6 and will likely also be
+> maintained in the future with the help of AI to ensure a consistent tone of
+> voice, style, and quality.
+> 
+> All contents have been reviewed by humans but there might still be some
+> mistakes left. That would put it in good company since the artisanal,
+> hand-crafted spec.yaml, that contains the TOML config specification, contains
+> plenty of mistakes as well.
+> 
+> The writing is of high quality in my estimation, certainly better than what I
+> would have produced in any reasonable amount of time. There are few obvious
+> _slop_ indicators. The AI sometimes uses superlatives ("ideal", "best") that I
+> would not use myself, but I've seen this style in other pieces of
+> documentation, so maybe it is just a style that aims to be approachable or to
+> guide users towards good solutions.
+> 
+> If you find something objectionable in this book, do not hesitate to open an
+> issue.
+
+Jay is a Wayland compositor for Linux with an i3-inspired tiling layout. It
+supports Vulkan and OpenGL rendering, multi-GPU setups, fractional scaling,
+variable refresh rate (VRR), tearing presentation, HDR, and screen sharing via
+xdg-desktop-portal. X11 applications are supported through Xwayland.
+
+Jay is configured through a declarative TOML file, with an optional advanced
+mode that uses a shared library for programmatic control. A built-in
+[control center](control-center.md) (opened with `alt-c`) provides a full GUI
+for inspecting and changing compositor settings at runtime -- including output
+arrangement, input devices, color management, GPU selection, and more. A
+comprehensive command-line interface makes scripting and automation
+straightforward.
+
+See the [Features](features.md) chapter for a comprehensive overview of what
+Jay can do, or jump straight to [Installation](installation.md) to get started.
+
+## License
+
+Jay is free software licensed under the
+[GNU General Public License v3.0](https://www.gnu.org/licenses/gpl-3.0.html).
+
+## Community
+
+[Discord server (unofficial)](https://discord.gg/Hby736z28G)