Variable: PUSH_PAYLOAD_VERSION ​
ts
const PUSH_PAYLOAD_VERSION: 1 = 1;Defined in: pushCrypto.ts:20
End-to-end encryption for push notifications.
Each phone makes a secret when it registers and gives it to its instance. The backend seals every notification for that phone with it (AES-256-GCM), and the phone opens it to build what it shows. The relay, Google and Apple carry only ciphertext.
The wire format is base64url(nonce ‖ ciphertext ‖ tag), which is also CryptoKit's AES.GCM.SealedBox.combined: the iOS notification service extension opens it natively. Pure JavaScript, so the same code runs in the backend and in the app's background task.