Sign and verify a message

sign.pl

use v5.20;
use warnings;

use Bitcoin::Crypto qw(btc_prv);

my $wif = 'KzTvd4uwnyRsFyoyTUWicxvP1HVQhTfsNLGVeyZSD6eajpTYvaRk';

my $private_key = btc_prv->from_wif($wif);
my $message = 'I own this Bitcoin address! ' . $private_key->get_public_key->get_legacy_address;
my $signature = $private_key->sign_message($message);

say 'Message is      ' . $message;
say 'Signature is    ' . unpack 'H*', $signature;
say 'Verification is ' . ($private_key->get_public_key->verify_message($message, $signature) ? 'successful' : 'unsuccessful');