$secureRandom = self::getSecureRandom();
$private = curve25519_private($secureRandom);
$public  = curve25519_public($private);
$keyPair = new ECKeyPair(new DjbECPublicKey($public),new DjbECPrivateKey($private));
        
$agreement = curve25519_shared( $keyPair->getPrivateKey(),$keyPair->getPublicKey());
$signature = curve25519_sign(getSecureRandom(64), $signingKey->getPrivateKey(), $message);
$verified  = curve25519_verify($signingKey->getPublicKey(), $message, $signature) == 0;