A UI component system
that scales with AI.

Full shadcn semantic token model. 43 tweakcn presets ship as drop-in theme files - swap one and every component updates instantly; light and dark are two palettes of one identity (the same radius in both, gated).

Every component ships a structured skill, every interactive one also a *.schema.json contract. Install skills/defuss-shadcn/SKILL.md in your agent - it carries every component skill with it. Three task skills plan UI, write themes and review markup, with bundled checkers.

Interactive components expose a State API (el.api.setState('open')), so agents and tests can drive every documented state by name.

Built on native HTML elements and WAI-ARIA patterns (menus and menubars with nested submenus, tabs, dialogs, trees, comboboxes, one-time-code fields, virtualized lists). Keyboard navigation, focus management, and screen reader support by default - and every theme preset's nav text is contrast-gated (WCAG AA) by verify.

Plain HTML, CSS and ES modules - no framework, no build pipeline, and 169 of 232 components need no JavaScript at all. The interactive ones run on one tiny core runtime, df$: defuss-query for DOM selection and events and defuss-morph for HTML reconciling, plus the shared State API helpers - shipped once as core.js, inside all.js. The footprint (counts per type, JS/CSS-only split, byte sizes) is published as dist/stats.json.