src/Derivation/HdNode.php
public static function newMasterNode($entropy)
    {
        $hmac = hash_hmac('sha512', $entropy, 'ed25519 seed', true);

        return new HdNode(
            substr($hmac, 0, 32),
            substr($hmac, 32, 32)
        );
    }
public static function newMasterNode($entropy)
    {
        $hmac = hash_hmac('sha512', $entropy, 'ed25519 seed', true);

        return new HdNode(
            substr($hmac, 0, 32),
            substr($hmac, 32, 32)
        );
    }
Returns a new master node that can be used to derive subnodes

@param $entropy
@return HdNode