Adi2

Adi2 is a widget toolkit written natively in Ada on top of SDL3. Layouts are declared in XML and styled with a CSS-like syntax that supports selectors, pseudo-classes, transitions, gradients and box shadows, and edits reload live without recompiling. It also ships animations, SVG and Lottie graphics, internationalization and asset bundling. The project describes itself as in production use but not yet at a stable release, so APIs can still change between versions.