Crypto

WebCrypto random values on native

Hermes ships no WebCrypto, so One installs crypto.getRandomValues and crypto.randomUUID (RFC 4122 v4) on native at startup. Both are synchronous calls straight into C++ over the system’s secure random generator (arc4random_buf on iOS and Android): getRandomValues fills your array in place without copying, and randomUUID is a single native call.

const id = crypto.randomUUID()
const bytes = crypto.getRandomValues(new Uint8Array(16))

Only missing pieces are installed: a runtime that already implements them keeps its own. There is no fallback to Math.random: a missing native module throws instead of returning weak bytes.