# Add CLItrail to Svelte + Vite (single-page app)
Where the CLItrail tag goes in Svelte + Vite (single-page app), in its own idiom, with the consent, CSP and client-side routing details and how to check it works.
Written for Svelte 5, Vite 8
## Where the tag goes
Edit `index.html`. Put the tag on every page that shows your install command; site-wide is best, after your existing analytics tags.
```html
```
## Only after consent
Use the loader in place of the tag: nothing from CLItrail loads until `startClitrail()` runs. Load the loader before your consent manager's script and call `startClitrail()` from the manager's accept callback (most managers also run it on later visits once a choice is stored; check yours). Use the marketing category when installs go to Google Ads, Meta, TikTok or X Ads, and the analytics category when they only reach GA4 or your webhooks.
Consent loader
```js
// Loads CLItrail only after the visitor agrees. Call startClitrail() from your
// consent manager's "accepted" callback; nothing is fetched or stored before that.
window.startClitrail = () => {
if (document.getElementById('clitrail')) return;
const tag = document.createElement('script');
tag.id = 'clitrail';
tag.src = 'https://YOUR_SERVICE/browser.js';
tag.dataset.website = 'YOUR_WEBSITE_ID';
document.head.append(tag);
};
```
```html
```
## Client-side routing
Svelte has no built-in router. Whichever one you use, the component that shows your install command mounts when that page opens: call `recordVisit()` in its `onMount`. Hash routers (`#/install`) keep one page path, so the visit recorded on load covers them.
Route helper
```js
// Records a visit when client-side navigation opens a new page path. The tag records
// the page the browser loaded, so that page is never recorded twice; before the SDK has
// started (for example, before consent) it records nothing.
let recorded;
export function recordVisit() {
if (typeof window === 'undefined') return;
recorded ??= new URL(performance.getEntriesByType('navigation')[0]?.name ?? location.href).pathname;
const sdk = window.InstallAttribution;
if (!sdk?.ready || location.pathname === recorded) return;
recorded = location.pathname;
sdk.ready = sdk.init({ service: 'https://YOUR_SERVICE', project: 'YOUR_WEBSITE_ID' });
}
```
```html
```
## Content Security Policy
Your host's header settings (for example `_headers` on Cloudflare Pages or Netlify, `vercel.json`, or your server), or a `` tag: add `https://YOUR_SERVICE` to `script-src` and `connect-src`, and `blob:` to `worker-src` (only Safari before 26 needs that one).
```
script-src 'self' https://YOUR_SERVICE;
connect-src 'self' https://YOUR_SERVICE;
worker-src 'self' blob:;
```
## Verify it works
1. Run `npm run dev` (http://localhost:5173) or deploy.
2. Open a page with the tag in Chrome or Firefox (accept analytics first if you gate CLItrail on consent), open the developer console and run `await InstallAttribution.ready`. It resolves to `{ ok: true, urlId, hasAnalyticsContext, expiresAt }`.
3. In the CLItrail dashboard, open Visits & identities: the visit is listed.
4. Anything else names the cause: `disabled` (no consent yet, or `data-enabled="false"`), `opfs_unavailable` (the page is not served over https or from localhost), `Error` (the service refused the visit: add the page's origin, including a development origin such as `http://localhost:3000`, under Settings → Additional domains). If `InstallAttribution` is undefined, the tag did not load: check the Network tab and your Content-Security-Policy.
Then run your installer on the same computer and check **Install events**, or run the hook with [`--doctor`](https://clitrail.com/docs/doctor).
Svelte + Vite (single-page app) documentation: [svelte.dev/docs/svelte/lifecycle-hooks](https://svelte.dev/docs/svelte/lifecycle-hooks)
Using other install paths or destinations? The [setup generator](https://clitrail.com/docs/setup-generator) puts this snippet together with your hooks and destination checklist.