| Core UI | Platform-agnostic widgets and helpers: GuiElement, GuiWindow, GuiButton, GuiImage, GuiText, GuiSound, GuiTrigger, the file/option browsers and the on-screen keyboard |
| Shapes and geometry | Platform-agnostic tessellation of rounded rectangles, ellipses, polygons, strokes, arcs, gradients and soft shadows into anti-aliased triangle meshes (GuiMesh) |
| Layout | Containers that position and size their children from rules instead of pixel offsets: GuiRow, GuiColumn, GuiGrid and GuiOverlay (options per child in GuiItem), plus the platform-agnostic solver behind them and selection navigation across nested containers |
| Builders | Describe a screen instead of assembling it: UiScope creates and owns a page's elements and runs per-frame bindings, and GuiLabel, GuiChip, GuiTextButton and GuiCard are themed widgets with no image assets that report clicks and focus through callbacks |
| Controller drawing | A controller drawn from shapes and described as a table (GuiControllerLayout), with a view that lights controls up and highlights them (GuiControllerView) and small control icons (GuiGlyph) |
| Platform abstraction | The Platform composition root and the video, audio and thread driver interfaces the core library is written against |
| Input | Per-frame input snapshots (InputPadData), the per-channel InputController, the InputDriver interface and pointer smoothing |
| Storage and network shares | FileSystemDriver device enumeration/mount/hot-plug and the SMB network-share driver |
| Threading and timing | Thread, Mutex, Cond and SystemTime - the wrappers app and library code use instead of a platform's raw threading API |
| Logging | The multi-backend Logger, its LOG_*() macros and every logging backend (console, UDP, USB Gecko/serial, file) |
| ▼Platform implementations | Concrete drivers behind the abstract interfaces |
| GameCube and Wii | GX video, AESND audio, PAD/WPAD input, LWP threads, FAT/DVD storage and libsmb2 - shared by both consoles (libogc2) |
| Wii U | GX2 video (with its custom shaders), AX audio, VPAD/KPAD input, coreinit threads, FSA/libmocha/libdvm storage and libsmb2 (wut) |