WIT, the Wii Interface Toolkit, is an event-driven C++-based development toolkit intended for Wii software development.

The intent of WIT is to encapsulate most of the mundane details of the Wii platform behind a consistent programming interface while remaining relatively lightweight. The Wii Remote and Nunchuk, the Classic Controller, GameCube controllers, and the Guitar Hero 3 controller are all managed through the same event system, allowing all forms of input to be handled consistently without requiring the developer to write separate code for each controller type. The Balance Board accessory is also supported. WIT’s design is inclusive, allowing the developer to use native API calls and third-party libraries without restriction or interference.

A secondary goal is to be the most thoroughly documented homebrew library available. Every constant, function, and class exposed by the WIT API is fully documented.

The current implementation of WIT is based on libOGC, but the toolkit API is backend-independent and should be readily portable to the official WiiWare SDK; likewise, a desktop-based Wii simulator using native graphics and input backends (perhaps through wiiuse or simulating the Wii Remote with a mouse) would be possible.