GitHub - BitcoinPHP/BitcoinECDSA.php: PHP library allowing ... Jul 07, 2017 · WARNING. This piece of software is provided without warranty of any kind, use it at your own risk. REQUIREMENTS. php 5.4.0 or newer.. php5-gmp needs to be installed.. If you want to launch the test file you need to be under a unix system with libbitcoin intalled on it.