cookie consent for SvelteKit
cookiecrumbsHandle inserts the tag as the first element of every HTML response’s head and sets event.locals.consent for your load functions.
the rule
A SvelteKit app loads its trackers from +layout.svelte on the client. No consent step, no record.
The rule is the same everywhere in the EU and the UK: nothing beyond what is strictly necessary may be stored on or read from a visitor’s device before they have agreed. That is Article 5(3) of the ePrivacy Directive, and the agreement has to meet the GDPR’s definition of consent: freely given, specific, informed and unambiguous, with a refusal that is as easy as the acceptance. The UK keeps the same rule in PECR, with narrow exemptions for low-risk statistics since 5 February 2026. California and the other US state laws work the other way round: no opt-in, but an opt-out link and support for the Global Privacy Control signal.
Three things follow for a website. Analytics, advertising and social scripts have to wait for a choice. The choice has to be recorded in a way you can show later, because Article 7(1) puts the burden of proof on you. And withdrawing has to be as easy as agreeing, which means a control that reopens the banner on every page. A banner that shows two buttons and loads Google Analytics anyway fails the first test, and that is the failure regulators have been fining, from the CNIL’s decisions against Google and SHEIN to the Dutch and Belgian authorities’ sweeps.
how it works
SvelteKit renders HTML through hooks.server.ts, and that is the cleanest place to put a consent runtime: a handle that transforms every HTML response and writes the tag first in the head, whatever the page or layout does. Compose it with your other hooks through sequence(); put %cookiecrumbs.head% in app.html if you want to choose the exact position yourself.
The same hook sets event.locals.consent, so a +page.server.ts load function can decide server-side whether to include an embed or its placeholder. On the client, consent stores keep every component in step: $consent for the categories, $regime for the applicable rule, and actions to open, accept, reject or withdraw.
SvelteKit’s onMount is where trackers tend to start. Wrap the subtree in ConsentGate, or check the store before initialising. Anything the scan finds on the deployed domain that is not tagged is handled by the block map, so a forgotten script in a legacy layout still waits.
set-up
Five steps. The CLI does most of them, and every one is also a click in the dashboard.
Detects SvelteKit, links the site, writes the config.
npx cookiecrumbs login
npx cookiecrumbs initCompose it with your other hooks through sequence(). Put %cookiecrumbs.head% in src/app.html to pick the exact position yourself.
npm i @cookiecrumbs/sveltekit
// src/hooks.server.ts
import { cookiecrumbsHandle } from '@cookiecrumbs/sveltekit/server';
export const handle = cookiecrumbsHandle({ site: 'pk_live_…', env: 'production' });ConsentGate, CookieDeclaration and ManageCookiesLink Svelte components and consent stores ship with the package.
<script>
import { ConsentGate } from '@cookiecrumbs/sveltekit';
</script>
<ConsentGate category="marketing">
<MetaPixel />
</ConsentGate>A load function can read the consent and skip an embed for visitors who said no, before any client code runs.
// +page.server.ts
export const load = ({ locals }) => ({
showMap: locals.consent?.isGranted('marketing') ?? false,
});Scan, sort once per vendor, publish.
npx cookiecrumbs scan --wait
npx cookiecrumbs push --env productionSvelteKit apps with Google Ads usually add gtag in app.html. Below the runtime, it loads with denied defaults and updates the moment someone chooses.
Google Consent Mode v2 is the signalling layer between the banner and Google’s tags. Before any tag runs, seven signals (ad_storage, analytics_storage, ad_user_data, ad_personalization, functionality_storage, personalization_storage, security_storage) are set to denied for visitors in the EEA, the UK and Switzerland. The moment someone chooses, the runtime updates them and Google’s tags adjust. Since 15 June 2026, Google uses ad_storage as the controlling signal for Ads data, so getting the default right matters more than it used to.
CookieCrumbs sets the defaults synchronously, ahead of any tag manager, updates them on every decision, and ships a Google Tag Manager template so the consent triggers exist without hand-written listeners. In advanced mode, Google’s cookieless pings keep modelled conversions working for the visitors who said no. What it does not do is pretend to be a Google-certified CMP: for AdSense, Ad Manager or AdMob in the EEA you still need one with IAB TCF, and CookieCrumbs is not that today.
watch out
Each one shows up in the first scan as a tracker that fired before consent.
before you ship
Eight lines. The dashboard ticks the last two from real data.
type="text/plain" with a category, or the host is in the block map from the scan.what you get
Two domains, 100 subpages scanned a month per domain, every regulation, the CLI, the SDKs and the MCP server.
Every page, in each consent state, in a real browser. Cookies, pixels, iframes and storage keys, with the page and script that set them. Re-scanned on a schedule.
The cookie declaration writes itself from the result.
Tags stay inert until their category is granted. Reject all is as visible as Accept all. Seven layouts, 25 languages, Consent Mode v2, and the right rule per region.
21 kB, one file, no third-party requests of its own.
Each choice is stored with a timestamp, the banner version and a hash of the texts shown, chained to the record before it. Exports are signed. Hosted in Frankfurt.
Article 7(1), on the free plan.
free check
The homepage HTML, matched against the tracker database. No account, nothing stored. The full scan in the dashboard does the same for every page, in a real browser.
questions
next step
Add the site, run npx cookiecrumbs init in your SvelteKit repo, and the consent log starts recording in the EU.