Pixel-perfect skeleton loading screens, extracted from your real UI. No manual measurement, no hand-tuned placeholders.
Works with React, Preact, Vue, Svelte 5, Angular, and React Native.
npm install boneyard-jsimport { Skeleton } from 'boneyard-js/react'
function BlogPage() {
const { data, isLoading } = useFetch('/api/post')
return (
<Skeleton name="blog-card" loading={isLoading}>
{data && <BlogCard data={data} />}
</Skeleton>
)
}<script setup>
import Skeleton from 'boneyard-js/vue'
import './bones/registry'
const loading = ref(true)
</script>
<template>
<Skeleton name="card" :loading="loading">
<Card />
</Skeleton>
</template><script>
import Skeleton from 'boneyard-js/svelte'
import '$lib/bones/registry'
let loading = true
</script>
<Skeleton name="card" {loading}>
<Card />
</Skeleton>import { Skeleton } from 'boneyard-js/preact'
function BlogPage() {
const { data, isLoading } = useFetch('/api/post')
return (
<Skeleton name="blog-card" loading={isLoading}>
{data && <BlogCard data={data} />}
</Skeleton>
)
}import { SkeletonComponent } from 'boneyard-js/angular'
@Component({
imports: [SkeletonComponent],
template: `
<boneyard-skeleton name="card" [loading]="isLoading">
<app-card />
</boneyard-skeleton>
`
})import { Skeleton } from 'boneyard-js/native'
<Skeleton name="profile-card" loading={isLoading}>
<ProfileCard />
</Skeleton>npx boneyard-js build --native --out ./bones
# Open your app on device — bones capture automaticallyDynamic Type: Generate bones at default font scale. Boneyard automatically scales bone positions at runtime to match the user's text size setting.
# CLI — works with any framework
npx boneyard-js build
# Watch mode — re-captures on HMR changes
npx boneyard-js build --watch
# React Native — scans from device
npx boneyard-js build --nativeThen import the registry once in your app entry:
import './bones/registry'For Vite-based projects (React, Preact, Vue, Svelte), use the plugin instead of the CLI — no second terminal needed:
// vite.config.ts
import { boneyardPlugin } from 'boneyard-js/vite'
export default defineConfig({
plugins: [boneyardPlugin()]
})Bones are captured automatically when the dev server starts and re-captured on every HMR update.
Web: The CLI (or Vite plugin) opens a headless browser, visits your app, finds every <Skeleton name="...">, and snapshots their layout at multiple breakpoints.
React Native: The <Skeleton> component auto-scans in dev mode when the CLI is running. It walks the fiber tree, measures views via UIManager, and sends bone data to the CLI. Zero overhead in production.
All frameworks output the same .bones.json format — cross-platform compatible.
| Flag | Default | Description |
|---|---|---|
[url] |
auto-detected | URL to visit |
--breakpoints |
375,768,1280 | Viewport widths, comma-separated |
--wait |
800 | ms to wait after page load |
--out |
./src/bones | Output directory |
--force |
— | Skip incremental cache |
--watch |
— | Re-capture on HMR changes |
--native |
— | React Native device scanning |
--no-scan |
— | Skip filesystem route scanning |
--cdp |
— | Connect to existing Chrome via debug port |
--env-file |
— | Load env vars from file |
| Prop | Type | Default | Description |
|---|---|---|---|
loading |
boolean | — | Show skeleton or real content |
name |
string | — | Unique name (generates name.bones.json) |
color |
string | rgba(0,0,0,0.08) |
Bone fill color |
darkColor |
string | rgba(255,255,255,0.06) |
Bone color in dark mode |
animate |
'pulse' | 'shimmer' | 'solid' |
'pulse' |
Animation style |
stagger |
number | boolean |
false |
Stagger delay between bones in ms (true = 80ms) |
transition |
number | boolean |
false |
Fade out duration when loading ends (true = 300ms) |
boneClass |
string | — | CSS class applied to each bone element |
fixture |
ReactNode / Snippet / Slot | — | Mock content for CLI capture (dev only) |
initialBones |
ResponsiveBones | — | Pass bones directly (overrides registry) |
fallback |
ReactNode / Snippet / Slot | — | Shown when loading but no bones available |
{
"breakpoints": [375, 768, 1280],
"out": "./src/bones",
"wait": 800,
"color": "#e5e5e5",
"animate": "pulse"
}Save as boneyard.config.json. Per-component props override config values.
| Import | Use |
|---|---|
boneyard-js |
snapshotBones, renderBones, computeLayout |
boneyard-js/react |
React <Skeleton> |
boneyard-js/preact |
Preact <Skeleton> (no compat needed) |
boneyard-js/vue |
Vue <Skeleton> |
boneyard-js/svelte |
Svelte <Skeleton> |
boneyard-js/angular |
Angular <boneyard-skeleton> |
boneyard-js/native |
React Native <Skeleton> |
boneyard-js/vite |
Vite plugin boneyardPlugin() |
MIT
