> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bily.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Choose your framework
> Install Bily once in your framework and track every committed route without duplicates.
The Bily JavaScript SDK works across browser applications because it owns one small contract: load one exact tracking URL, record the initial page automatically, and track only later client-side routes yourself.
## Find your installation path
| Website | Start Bily in | Observe later routes with |
| ------------------------------------ | ------------------------------------------- | ------------------------------------------- |
| Plain HTML | Shared `` | A new document loads the script again |
| Vanilla JavaScript | Browser entry module | Your router's committed-navigation callback |
| React Router | One component inside the existing router | `useLocation()` |
| Next.js | One shared client component | `usePathname()` and `useSearchParams()` |
| Vue | Browser bootstrap after the router is ready | `router.afterEach()` |
| Nuxt | One client plugin | `useRouter().afterEach()` |
| Svelte | Browser entry module | Your router's committed-navigation callback |
| SvelteKit | Root layout component | `afterNavigate()` |
| Angular | One root service | `NavigationEnd` |
| Astro | Shared layout script | Persisted script plus `astro:page-load` |
| React Router framework mode or Remix | One component in the root route | `useLocation()` |
## Choose a guide
Add the exact browser script to every document through one shared layout.
Initialize from a browser entry module and connect your router callback.
Mount one tracking component inside the router you already use.
Cover App Router, Pages Router, or both with one shared component.
Wait for the initial route, then observe successful navigations.
Start Bily from one client plugin after the first page finishes.
Use the browser entry for Svelte or the root layout for SvelteKit.
Subscribe once to successful Angular Router navigation.
Support full document loads and optional client-side transitions.
Add one component to the root route without replacing its document shell.
## Keep one contract everywhere
Every framework follows the same rules:
1. Copy the complete tracking URL from **Bily > Settings > Apps > More settings > Install tracking**.
2. Let `@bilyai/js` own the loader unless a framework guide reserves one script element for the SDK to reuse. Never add a second unmanaged tag.
3. Let the browser script record the initial `PageView`.
4. Send one explicit `PageView` after each later committed client-side route.
5. Ignore repeated notifications when `window.location.href` has not changed.
The package ships ESM, CommonJS, and TypeScript definitions with no runtime dependencies. Its public methods can be imported during server rendering; browser work starts only from client-mounted code.
The tracking URL is public installation data, not a private token. Keep private credentials out of browser configuration and event payloads.
Prove the script, initial page, later routes, and action events appear once.
Replace the complete tracking URL after Bily validates your customer subdomain.