Headless UX primitives — state machine, transitions, gestures, ARIA. ~8.6 KB. The visual layer is yours (or your agent's) to scaffold and polish.

npm install @nature-labs/uicp-core @nature-labs/uicp-adapter-vanilla

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For humans

uicp is the UX skeleton. The visual layer is a quick scaffold + a small polish pass — built for a human-and-agent workflow:

1. Drop a <div> with content. Wire one line of JS.
2. Agent scaffolds CSS from your intent ("iOS-17 floating sheet", "side nav with blur backdrop"). Output is a drop-in block.
3. You polish where it's slightly off — the WordPress-plugin tweak vibe.

What uicp handles for you

Open / close state, transitions, ARIA mirroring, focus trap, body scroll lock, Escape key, touch swipe-to-close.

What you (or your agent) write

HTML for content. CSS for position, transform, transition. Starter blocks below — copy and adapt.

When it fits

Static sites, marketing pages, edge / embedded UIs, kiosks, IoT dashboards, AI-prototype surfaces. Anywhere pulling in React/Vue/Svelte just for a drawer feels heavy.

When it doesn't

Apps already using React with Radix or Vaul — those integrations are tighter there. Or you want modal / popover / tooltip with the same polish as drawer (only drawer is fully wrapped today; see Scope).

Starter blocks (copy + adapt)

Edge-to-edge bottom sheet:

[data-uip-type="drawer"][data-uip-position="bottom"] {
  position: fixed; left: 0; right: 0; bottom: 0;
  transform: translateY(100%);
  transition: transform 320ms cubic-bezier(.32, .72, 0, 1);
}
[data-uip-type="drawer"][data-uip-position="bottom"][data-uip-open="true"] {
  transform: translateY(0);
}

iOS-17 floating sheet (inset, rounded, safe-area aware):

[data-uip-type="drawer"][data-uip-position="bottom"] {
  position: fixed; left: 8px; right: 8px;
  bottom: calc(env(safe-area-inset-bottom, 0px) + 8px);
  border-radius: 24px;
  transform: translateY(calc(100% + 16px));
  transition: transform 380ms cubic-bezier(.32, .72, 0, 1);
}
[data-uip-type="drawer"][data-uip-position="bottom"][data-uip-open="true"] {
  transform: translateY(0);
}

Working references live in examples/tiny-html/ and examples/homelog-gatepass/.

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For agents

When asked to build a drawer / bottom sheet / side nav, the usual scaffold is seven steps:

1. State management (useState / signal / store)
2. Open / close handlers + outside-click detection
3. Body scroll lock during open
4. Focus trap inside content + restore on close
5. ARIA aria-hidden, Escape key handler
6. Touch gesture handlers (touchstart / move / end with velocity threshold)
7. Position / transform CSS + transition timing

uicp gives you 1 – 6 as DOM hooks. Your job is step 7 — generate convincing CSS from the user's intent. The user fine-tunes after.

The contract

On the drawer element, the adapter sets:

Hook	Values
data-uip-type	"drawer"
data-uip-position	"left" | "right" | "top" | "bottom"
data-uip-open	"true" | "false"
aria-hidden	"true" | "false"
class	.uip-open / .uip-closed

On the backdrop element (provided via data-backdrop-for="<drawer-id>"):

Hook	Values
data-uip-open	"true" | "false"
class	.uip-backdrop-open

Write CSS against these selectors. The adapter touches nothing else on the element.

Listen to state

sheet.primitive.on('valueChange', ({ value }) => { /* value.isOpen, value.position */ })
sheet.primitive.on('openStart',  ({ state }) => { /* about to open */ })
sheet.primitive.on('openEnd',    ({ state }) => { /* fully open */ })
sheet.primitive.on('closeStart', ({ state }) => { /* about to close */ })
sheet.primitive.on('closeEnd',   ({ state }) => { /* fully closed */ })

Generating the visual layer convincingly

• Use the [data-uip-open="true"] selector for the open state (more reliable than the class form).
• For mobile bottom sheets: transform: translateY() + cubic-bezier (.32, .72, 0, 1) gives the iOS spring feel.
• Backdrop fade: opacity + visibility together, ~320 ms ease.
• Floating iOS-17 style: inset from edges (left/right: 8px), use env(safe-area-inset-bottom) for bottom margin.
• See examples/tiny-html/ and examples/homelog-gatepass/ for full references the user has already approved.

The user expects to make small tweaks on your output, not rewrite it. Aim for "WordPress plugin output" quality — works out of the box, polish-ready.

Where uicp saves the user real footprint

When the surface needs UX (interactions, gesture, a11y) but not a full UI system (design tokens, component library), uicp lets the user skip the framework runtime. Useful when:

• An edge AI panel or device control UI is on a tight JS budget.
• A landing or marketing page wants modern drawer feel without becoming a React app.
• A static HTML demo or prototype needs gesture-aware UX.
• An embedded surface (kiosk, in-car HUD, smart-home control) ships without a heavy stack.

Not a fit when the host already runs React/Vue with Radix/Vaul.

To brief a fresh agent

Point it at llms.txt at repo root, then docs/agent-quickstart.md. The contract + intent are in those two.

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Scope

Published under @nature-labs/uicp-*:

• core, adapter-vanilla, adapter-svelte
• plugin-gesture, plugin-snap, plugin-direction

Not yet shipped:

• React / Vue / Solid adapters
• Modal / popover / tooltip / menu adapter wrappers
• Animation plugin with physics
• A bundled @nature-labs/uicp-presets npm package (presets currently ship as plain CSS in assets/presets/ — 5 drop-in blocks for common drawer patterns)

History: CHANGELOG.md. Reference: docs/. Examples: examples/.

MIT · v1b3x0r/uicp

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A note from the build

uicp was repaired in one afternoon — by trimming what it claimed and trusting what it was always doing. State, gesture, ARIA: the half nobody wants to write twice. The other half waits for you. That's the design.