Shadcn Baseui

shadcn/ui + Base UI Guidelines

A guide for using shadcn/ui components when working with Base UI. Prevents LLMs from incorrectly suggesting Radix UI patterns (asChild, etc.).

⚠️ CRITICAL: Before suggesting any code, verify this is a Base UI project by checking components.json. The style field should start with "base-" (e.g., "base-vega", "base-nova", "base-maia", "base-lyra", "base-mira"). If it starts with something else, this skill does not apply.

Ensure the @base-ui/react package is installed. If not, install it using the appropriate package manager.

Slot Pattern

The major difference between Radix UI and Base UI is the slot pattern. Radix UI uses asChild, while Base UI uses the render prop. Always use render prop over asChild.

Rule: Always use render prop instead of asChild for ALL trigger/wrapper components.

Applies to: DialogTrigger, AlertDialogTrigger, PopoverTrigger, DropdownMenuTrigger, TooltipTrigger, SelectTrigger, TabsTrigger, AccordionTrigger, Button (when wrapping links), etc.

// ❌ INCORRECT
<DialogTrigger asChild>
  <Button variant="outline">Click me</Button>
</DialogTrigger>

// ✅ CORRECT
<DialogTrigger render={<Button variant="outline" />}>
  Click me
</DialogTrigger>

// ✅ ALSO CORRECT
<DialogTrigger render={<Button variant="outline">Click me</Button>} />

Props

Beyond the slot pattern, only the following components have different props. When using these components following the component specific guide.

Accordion

There's no type prop on the Accordion component, use the boolean multiple prop instead. The defaultValue prop is always array based.

1. Single Mode

// ❌ INCORRECT
<Accordion type="single" defaultValue="item-1">
  <AccordionItem value="item-1">
    // ...
  </AccordionItem>
</Accordion>

// ✅ CORRECT
<Accordion defaultValue={["item-1"]}>
  <AccordionItem value="item-1">
    // ...
  </AccordionItem>
</Accordion>

2. Multi Mode

// ❌ INCORRECT
<Accordion type="multiple" defaultValue={["item-1", "item-2"]}>
  <AccordionItem value="item-1">...</AccordionItem>
  <AccordionItem value="item-2">...</AccordionItem>
</Accordion>

// ✅ CORRECT
<Accordion multiple defaultValue={["item-1", "item-2"]}>
  <AccordionItem value="item-1">...</AccordionItem>
  <AccordionItem value="item-2">...</AccordionItem>
</Accordion>

Button (Special Case)

When rendering a Button as a non-button element (like a Link), you must add nativeButton={false}.

// ❌ INCORRECT - Radix pattern
import Link from "next/link";

<Button asChild variant="ghost">
  <Link href="/dashboard">Dashboard</Link>
</Button>

// ✅ CORRECT - Base UI pattern
import Link from "next/link";

<Button render={<Link href="/dashboard" />} variant="ghost" nativeButton={false}>
  Dashboard
</Button>

Select

The position prop is replaced with a boolean prop alignItemWithTrigger which defaults to true.

// ❌ INCORRECT
<SelectContent position="popper">
  // ...
</SelectContent>

// ✅ CORRECT
<SelectContent alignItemWithTrigger={false}>
  // ...
</SelectContent>