Opentui is a terminal user interface framework for building interactive command line applications. It provides a component-based system featuring a flexbox layout engine, a virtual node component tree, and a low-level 2D cell array renderer.
The project is distinguished by a sophisticated keyboard binding engine that maps complex multi-stroke sequences and chords to named commands using prioritized, reactive layers. It also implements a plugin architecture that allows external modules to inject custom UI components into designated layout slots and extend input logic at runtime.
Its capabilities cover rich text rendering—including syntax-highlighted code, markdown, and diff views—and advanced visual effects like alpha blending and RGBA matrix transformations. The framework includes a comprehensive input pipeline supporting the Kitty keyboard protocol, as well as a suite of interactive UI components such as multi-line text fields, selection menus, and value sliders.
The system can be compiled into a standalone executable with embedded native binaries for distribution.