# Heap

The c15t heap helper loads Heap only after visitors allow measurement in Inth. On withdrawal, c15t removes the config script and reloads the page to stop heap.js.

## Key facts

- **Tool:** Heap
- **Category:** Analytics
- **Consent categories:** Measurement
- **Setup method:** c15t package
- **Package:** @c15t/integrations

## Links

- [Documentation](https://c15t.com/docs/integrations/heap)
- [Heap](https://www.heap.io/)

Keep Heap off the page until visitors allow measurement. Calls that your code makes before heap.js is ready wait in a queue.

Inth keeps the consent record of each choice, with the visitor’s country and the policy that applied.

[Start for free](/dashboard/sign-up)

## Before you start

You need an Inth project that connects to your app, c15t in that app and the environment ID from your Heap installation snippet.

New to c15t? Complete the quickstart for your framework first. Keep its Inth endpoint, policy, styles and consent UI.

[Open the quickstart for your framework](https://c15t.com/docs/frameworks)

## How consent works with Heap

Before measurement has permission, c15t defines no window.heap and does not load heap\_config.js. That file loads the heap.js runtime.

After permission, the helper creates window.heap with stubs for the heap.js v5 methods. Then it loads the config script. heap.js replays the queued calls when it is ready.

The helper never calls heap.stopTracking. On withdrawal, c15t removes the config script and reloads the page by default. The reload stops heap.js.

If you turn reloadOnConsentRevoked off, call window.heap.stopTracking() from a callback-only script.

[Read about custom integrations](https://c15t.com/docs/integrations/building-integrations)

## Installation

Heap has one load mode in c15t. The helper waits for measurement permission.

### Wait for permission

No request goes to Heap until the visitor accepts measurement. On withdrawal, c15t removes the config script and reloads the page.

```ts
heap({ envId })
```

An opt-out policy or no policy gives optional categories permission before a choice. Then Heap loads on the first page. This guide uses an opt-in policy.

## Setup steps

#### Install the integration package

Add the helpers next to c15t. An import alone does not start Heap.

```
pnpm add @c15t/integrations
```

#### Add your environment ID

The helper sets the ID as heap.envId and heap.appid and loads heap\_config.js for that environment.

```
import { heap } from '@c15t/integrations/heap';

export const scripts = [heap({ envId: 'YOUR_ENVIRONMENT_ID' })];
```

An empty environment ID logs an error, and the script does not load. The helper always sets shouldFetchServerConfig to false.

### Register it with your existing setup

#### Next.js

Add scripts to c15t.config.ts, next to next.config.ts. Keep the rest of your config, such as mode, in the same call. App Router, Pages Router and static export read the same file.

```
import { defineConsentConfig } from 'c15t/next';
import { scripts } from './src/consent-scripts';

export default defineConsentConfig({ scripts });
```

#### TanStack Start

Pass scripts to the ConsentRoot in your root route. Import helpers in the route module, not in a server function: script configurations carry callbacks.

```
import { scripts } from '../consent-scripts';

<ConsentRoot state={consent} scripts={scripts}>
```

#### React

Add scripts to the options of your ConsentProvider, next to mode. Keep the banner, dialog and preferences link inside the provider.

```
import { scripts } from './consent-scripts';

<ConsentProvider options={{ mode, scripts }}>
```

#### Nuxt

Register scripts under the c15t key in app.config.ts. Keep them out of nuxt.config.ts, which reaches the browser as JSON and drops the helper callbacks.

```
import { scripts } from '../src/consent-scripts';

export default defineAppConfig({
  c15t: { scripts },
});
```

#### Vue

Pass scripts to the c15tVue plugin call you have now. The plugin starts one script loader when the app mounts.

```
import { c15tVue, manifest } from 'c15t/vue/vue-plugin';
import { scripts } from './consent-scripts';

app.use(c15tVue, {
  mode: manifest(),
  scripts,
});
```

#### Astro

Add scripts to the client entrypoint, which the integration finds on its own. Keep helpers out of astro.config.mjs: its options are serialized into the page.

```
import type { C15tClientOptionsExtension } from 'c15t/astro';
import { scripts } from './consent-scripts';

export default { scripts } satisfies C15tClientOptionsExtension;
```

#### Svelte

Pass scripts as a prop to the ConsentProvider you have now. The provider owns the loader and disposes it on unmount.

```
<script lang="ts">
  import { ConsentProvider, manifest } from 'c15t/svelte';
  import { scripts } from './consent-scripts';
</script>

<ConsentProvider mode={manifest()} {scripts}>
  <!-- Your app and consent UI -->
</ConsentProvider>
```

#### SvelteKit

Add scripts to the ConsentRoot in the root layout. Import helpers in the layout component, not in +layout.server.ts: a server load cannot send functions to the browser.

```
<script lang="ts">
  import { ConsentRoot } from 'c15t/svelte';
  import { scripts } from '../consent-scripts';

  let { children, data } = $props();
</script>

<ConsentRoot state={data.consent} {scripts}>
  {@render children()}
</ConsentRoot>
```

#### HTML: Paste the vendor’s snippet behind consent

The helpers need a bundler. On a page with the c15t script tag, paste the vendor’s own snippet instead and keep it inert until visitors allow its category. Helper options, such as loadMode, do not apply.

```
<script type="text/plain" data-c15t-category="measurement">
  // The vendor's snippet, unchanged
</script>
```

#### JavaScript

Pass scripts to init() from @c15t/browser, next to your mode. With createConsentRuntime, pass scripts to it instead.

```
import { init, manifest } from '@c15t/browser';
import { scripts } from './consent-scripts';

const consent = init({
  mode: manifest(),
  scripts,
});
```

Remove the old Heap snippet, so Heap loads only through c15t. If you already have a scripts array, add the helper to it.

## Verify your setup

Use a private window with an opt-in policy. Open DevTools Network and filter by heap. Then test the three states.

- **Before a choice**: No request goes to cdn.us.heap-api.com. In the Console, window.heap returns undefined.

- **After you allow measurement**: heap\_config.js for your environment ID loads, and then the heap.js runtime. window.heap.envId holds your environment ID.

- **After you withdraw measurement**: Save your choice. c15t reloads the page. The new page sends no request to Heap.

Keep the reload on. Without it, heap.js continues to capture until the page unloads.

[Open the full Heap guide](https://c15t.com/docs/integrations/heap)

## Related guides

- [Mixpanel](/integrations/mixpanel-analytics)

- [Pendo](/integrations/pendo)

- [PostHog](/integrations/posthog)