Add eager GCM bootstrap and remove PostHog integration

GCM now creates dataLayer and denies all consent types before the
config fetch, closing the gap where gtag could track freely during
the async config load. PostHog integration is removed because
script blocking via data-cookie-consent is the correct mechanism
for vendors that don't support a queue/replay pattern.

Signed-off-by: Émile Ré <emile@probo.com>

packages/cookie-banner/src/client.ts

@@ -79,6 +79,10 @@ export class CookieBannerClient {
   }
 
   async load(): Promise<void> {
+    for (const integration of this.integrations) {
+      integration.bootstrap();
+    }
+
     const configUrl = new URL(`${this.bannerId}/config`, this.baseUrl);
     if (this.lang) {
       configUrl.searchParams.set("lang", this.lang);
@@ -89,6 +93,8 @@ export class CookieBannerClient {
       config = await fetchJSON<BannerConfig>(configUrl);
     } catch {
       this.startDetector();
+      this.observer = observeAndActivate({}, {});
+      getConsent()._setReady({}, false);
       return;
     }
     this.bannerConfig = config;

packages/cookie-banner/src/integrations/gcm.ts

@@ -22,14 +22,16 @@ export class GoogleConsentModeIntegration implements ConsentIntegration {
     );
   }
 
-  private getConsentFn(): ((...args: unknown[]) => void) | null {
+  private getConsentFn(): (...args: unknown[]) => void {
     const w = window as unknown as Record<string, unknown>;
 
     if (typeof w.gtag === "function") {
       return w.gtag as (...args: unknown[]) => void;
     }
 
-    if (!Array.isArray(w.dataLayer)) return null;
+    if (!Array.isArray(w.dataLayer)) {
+      w.dataLayer = [];
+    }
 
     const dataLayer = w.dataLayer as unknown[];
     return function () {
@@ -37,11 +39,23 @@ export class GoogleConsentModeIntegration implements ConsentIntegration {
     };
   }
 
+  bootstrap(): void {
+    const consentFn = this.getConsentFn();
+    consentFn("consent", "default", {
+      ad_storage: "denied",
+      ad_user_data: "denied",
+      ad_personalization: "denied",
+      analytics_storage: "denied",
+      functionality_storage: "denied",
+      personalization_storage: "denied",
+      security_storage: "denied",
+    });
+  }
+
   setDefaults(categories: Category[]): void {
     if (!this.hasMapping(categories)) return;
 
     const consentFn = this.getConsentFn();
-    if (!consentFn) return;
 
     const defaults: Record<string, string> = {};
     for (const cat of categories) {
@@ -63,7 +77,6 @@ export class GoogleConsentModeIntegration implements ConsentIntegration {
     if (!this.hasMapping(categories)) return;
 
     const consentFn = this.getConsentFn();
-    if (!consentFn) return;
 
     const update: Record<string, string> = {};
     for (const cat of categories) {

packages/cookie-banner/src/integrations/index.ts

@@ -14,15 +14,12 @@
 
 export type { ConsentIntegration } from "./integration";
 export { GoogleConsentModeIntegration } from "./gcm";
-export { PostHogIntegration } from "./posthog";
 
 import type { ConsentIntegration } from "./integration";
 import { GoogleConsentModeIntegration } from "./gcm";
-import { PostHogIntegration } from "./posthog";
 
 export function createDefaultIntegrations(): ConsentIntegration[] {
   return [
     new GoogleConsentModeIntegration(),
-    new PostHogIntegration(),
   ];
 }

packages/cookie-banner/src/integrations/integration.ts

@@ -15,6 +15,9 @@
 import type { Category } from "../types";
 
 export interface ConsentIntegration {
+  /** Called eagerly before config fetch to deny all tracking by default. */
+  bootstrap(): void;
+
   /** Called once after config is loaded, before any consent is applied. */
   setDefaults(categories: Category[]): void;
 

packages/cookie-banner/src/integrations/posthog.ts

@@ -1,69 +0,0 @@
-// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
-//
-// Permission to use, copy, modify, and/or distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
-// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
-// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
-// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
-// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
-// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-// PERFORMANCE OF THIS SOFTWARE.
-
-import type { Category } from "../types";
-import type { ConsentIntegration } from "./integration";
-
-interface PostHogInstance {
-  opt_in_capturing: () => void;
-  opt_out_capturing: () => void;
-}
-
-export class PostHogIntegration implements ConsentIntegration {
-  private hasMapping(categories: Category[]): boolean {
-    return categories.some((cat) => cat.posthog_consent);
-  }
-
-  private getPostHog(): PostHogInstance | null {
-    const w = window as unknown as Record<string, unknown>;
-    const posthog = w.posthog as (PostHogInstance & Record<string, unknown>) | undefined;
-    if (
-      !posthog ||
-      typeof posthog.opt_in_capturing !== "function" ||
-      typeof posthog.opt_out_capturing !== "function"
-    ) {
-      return null;
-    }
-    return posthog;
-  }
-
-  setDefaults(categories: Category[]): void {
-    if (!this.hasMapping(categories)) return;
-
-    const posthog = this.getPostHog();
-    if (!posthog) return;
-
-    posthog.opt_out_capturing();
-  }
-
-  update(
-    categories: Category[],
-    consentData: Record<string, boolean>,
-  ): void {
-    if (!this.hasMapping(categories)) return;
-
-    const posthog = this.getPostHog();
-    if (!posthog) return;
-
-    const granted = categories
-      .filter((cat) => cat.posthog_consent)
-      .every((cat) => !!consentData[cat.slug]);
-
-    if (granted) {
-      posthog.opt_in_capturing();
-    } else {
-      posthog.opt_out_capturing();
-    }
-  }
-}