Fatal error: Uncaught Error: Interface 'JsonSerializable' not found in /home/oraclescore/repo/vendor/locomotivemtl/charcoal-config/src/Charcoal/Config/EntityInterface.php:12 Stack trace: #0 /home/oraclescore/repo/vendor/composer/ClassLoader.php(576): include() #1 /home/oraclescore/repo/vendor/composer/ClassLoader.php(427): Composer\Autoload\{closure}('/home/oraclesco...') #2 [internal function]: Composer\Autoload\ClassLoader->loadClass('Charcoal\\Config...') #3 /home/oraclescore/repo/vendor/locomotivemtl/charcoal-config/src/Charcoal/Config/AbstractEntity.php(20): spl_autoload_call('Charcoal\\Config...') #4 /home/oraclescore/repo/vendor/composer/ClassLoader.php(576): include('/home/oraclesco...') #5 /home/oraclescore/repo/vendor/composer/ClassLoader.php(427): Composer\Autoload\{closure}('/home/oraclesco...') #6 [internal function]: Composer\Autoload\ClassLoader->loadClass('Charcoal\\Config...') #7 /home/oraclescore/repo/vendor/locomotivemtl/charcoal-config/src/Charcoal/Config/AbstractConfig.php(26): spl_autoload_call('Char in /home/oraclescore/repo/vendor/locomotivemtl/charcoal-config/src/Charcoal/Config/EntityInterface.php on line 12