deployer/recipe/deploy/cleanup.php

<?php
/* (c) Anton Medvedev <anton@medv.io>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Deployer;

desc('Cleaning up old releases');
task('cleanup', function () {
    $releases = get('releases_list');
    $keep = get('keep_releases');
    $sudo  = get('cleanup_use_sudo') ? 'sudo' : '';
    $runOpts = [];
    if ($sudo) {
        $runOpts['tty'] = get('cleanup_tty', false);
    }

    if ($keep === -1) {
        // Keep unlimited releases.
        return;
    }

    while ($keep > 0) {
        array_shift($releases);
        --$keep;
    }

    foreach ($releases as $release) {
        run("$sudo rm -rf {{deploy_path}}/releases/$release", $runOpts);
    }

    run("cd {{deploy_path}} && if [ -e release ]; then $sudo rm release; fi");
    run("cd {{deploy_path}} && if [ -h release ]; then $sudo rm release; fi");
});