Ghostty is a fast, native, feature-rich terminal emulator targeting macOS (SwiftUI/Metal) and Linux (GTK), with an embeddable C library, libghostty. The core is written in Zig, providing a complete VT parser, screen management, scrollback, selection, search, Kitty graphics protocol, and snapshot/restore. The macOS frontend uses SwiftUI and AppKit for window management, tabs, splits, quick terminal overlay, command palette, AppleScript, App Intents, and Sparkle-based updates. The Linux frontend uses GTK with Wayland/X11 support. The architecture is modular: a platform-independent terminal engine (src/terminal/) communicates with platform-specific app runtimes (src/apprt/) via a callback-based effects interface. The renderer supports Metal (macOS) and OpenGL (Linux) with SIMD-optimized text layout and custom font sprite drawing for powerline, box drawing, and Nerd Font glyphs. External dependencies include fontconfig, freetype, harfbuzz, oniguruma, libpng, and stb_image, all vendored and minimized. The build system uses Zig with Nix and CMake support. The library is designed for embedding, with examples in C, C++, Swift, Zig, and WebAssembly.