Swap In Redis as the cache store

concrete.php

<?php

return array(
    'debug' => array(
        'detail' => 'debug'
    ),
    'cache' => array(
        'levels' => array(
            'expensive' => array(
                'drivers' => array(
                    array(
                        'class' => '\Stash\Driver\Redis',
                        'options' => array(
                            'servers' => array(
                                array(
                                    'server' => $_SERVER['CACHE1_HOST'],
                                    'port'   => $_SERVER['CACHE1_PORT']
                                )
                            )
                        )
                    )
                )
            ),
            'object' => array(
                'drivers' => array(
                    array(
                        'class' => '\Stash\Driver\Redis',
                        'options' => array(
                            'servers' => array(
                                array(
                                    'server' => $_SERVER['CACHE1_HOST'],
                                    'port'   => $_SERVER['CACHE1_PORT']
                                )
                            )
                        )
                    )
                )
            )
        )
    )
);