textual

Textual is an open-source Python framework for building rich terminal user interfaces, or TUIs. It leverages the Rich rendering library to create modern, interactive console applications with widgets, layouts, and theming. Textual enables developers to compose user interfaces using a declarative approach, using components called widgets arranged in containers and grids, styled with a CSS-like language and responsive to terminal size.

Textual was created by Will McGugan and the Textualize community, with initial public releases around 2021, and has continued to evolve with active contributions. It is distributed under an open-source license (MIT) and is maintained on GitHub.

In terms of architecture, Textual runs on Python with asyncio and provides an App class as the entry point. Developers define the interface by subclassing App, implementing methods such as on_mount and compose to assemble widgets, and by handling events like on_key or on_click. Widgets expose properties that can be made reactive, enabling automatic updates when state changes. The styling system uses CSS-like selectors to apply visual properties such as color, margins, and layout, and supports themes.

Common widgets include buttons, inputs, scrollable views, data tables, tree views, markdown rendering, and tabbed panels. Layouts are achieved through containers and grids, with responsive behavior for different terminal sizes. Textual integrates with Rich for rich text rendering, progress bars, and live updating text.

Typical use cases are terminal dashboards, monitoring tools, editors, and interactive CLIs. The project emphasizes a modern development experience for terminal apps and has an active community and extensive documentation.

See also Rich, Urwid, and other Python UI toolkits.