Reduce bundle size

ConsentLayer is built so that your bundle contains only the parts you import. The package is ES modules only and declares "sideEffects": false, so any bundler that tree-shakes, such as Vite, Rollup, esbuild, webpack or Turbopack, drops the exports you don’t use. The package’s CI measures the entry points on every change; see Bundle size for the current figures.

Import only what you use

Each provider, consent adapter and server destination is its own entry point, and the root entry exports none of them. Importing ga4() never bundles meta() or posthog():

import { createAnalytics } from 'consentlayer'
import { ga4 } from 'consentlayer/providers/ga4'

A provider turned off by an undefined ID, such as meta({ pixelId: process.env.NEXT_PUBLIC_FACEBOOK_PIXEL_ID }) without the variable, still ships its code. To keep a provider out of the bundle, don’t import it.

From the root entry, only the exports you use are bundled; the bundle size table lists createAnalytics() on its own. The consent engine, the event queue and debug logging are part of createAnalytics() whether or not you turn them on. Auto-tracking is a separate entry, consentlayer/auto-tracking, bundled only when you import autoTracking().

Load vendor SDKs on demand

posthog() and sentry() load posthog-js and @sentry/browser with a dynamic import(), which your bundler splits into separate chunks, fetched only when the provider loads. PostHog session recording, Sentry Session Replay and Sentry tracing are further chunks, fetched only when you turn them on.

defer postpones loading these SDKs until the browser is idle, the first interaction or a delay, so they don’t compete with your page’s first load:

posthog({ apiKey: process.env.NEXT_PUBLIC_POSTHOG_KEY, defer: 'idle' })

See Loading SDKs later.

The other providers ship no SDK. Most inject their vendor’s script tag in the browser, from the vendor’s servers, once consent allows it. vercel() injects no script: it calls the track function you pass from @vercel/analytics.

Prefer npm over the script tag

The script tag bundles every provider and adapter into one file, because it can’t know which ones a page uses; its size is in the bundle size table. Installed from npm, you ship only the core and the providers you import.

Measure your own bundle

To see what ConsentLayer adds to your application, use your bundler’s analyzer, such as @next/bundle-analyzer or rollup-plugin-visualizer for Vite, and look for consentlayer in the output.