diff --git a/package.json b/package.json
index 44c8173..374f3fe 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,7 @@
     "build:prod": "npm run clean && rollup -c --environment NODE_ENV:production && tsc --project ./src/tsconfig.json",
     "deploy": "npm run build && gcloud app deploy dev.yaml --project=try-webauthn",
     "deploy:prod": "npm run build:prod && gcloud app deploy app.yaml --project=try-webauthn",
+    "gcp-build": "npm run build:prod",
     "dev": "NODE_ENV=localhost node dist/server.mjs",
     "emulator": "firebase emulators:start --only firestore,auth --project try-webauthn --import=./.data --export-on-exit",
     "start": "node dist/server.mjs"
diff --git a/src/libs/webauthn.mts b/src/libs/webauthn.mts
index 1576a9f..4e079af 100644
--- a/src/libs/webauthn.mts
+++ b/src/libs/webauthn.mts
@@ -74,8 +74,9 @@ export const getOrigin = (
           const octArray = hashes[i].split(':').map((h) =>
             parseInt(h, 16),
           );
+          const uint8Array = new Uint8Array(octArray.length);
           // @ts-ignore
-          const androidHash = base64url.encode(octArray);
+          const androidHash = isoBase64URL.fromBuffer(uint8Array);
           origin = `android:apk-key-hash:${androidHash}`;
           break;
         }