Must have custom drush commands in every Drupal project

/**
 * Implements drush_command().
 */
function my_module_drush_command() {
  $items = [];
  $items['my-module-run-db-checks'] = [
    'description' => 'Checking potential issues on the database to ensure it is production ready.',
    'callback' => 'my_module_run_db_checks',
    'examples' => [
      'drush my-module-db-checks' => 'Run few database checks on the respected target.',
    ],
    'aliases' => ['my-module-run-db-checks'],
  ];

  return $items;
}

/**
 * Run an audit against a database to check for potential issues.
 */
function my_module_run_db_checks() {
  $errors = [];

  // Hide all PHP errors.
  $er_query = db_query("SELECT CONVERT( value
    USING utf8 ) AS error_reporting_level
    FROM variable
    WHERE name = 'error_level'
    LIMIT 0 , 30
  ");
  $record = $er_query->fetchObject();
  $error_level = unserialize($record->error_reporting_level);
  if ($error_level !== "0") {
    $errors['php_errors_visible'] = 'PHP errors are not hidden. Errors will be visible on the site.';
  }

  // Check if there is any error found.
  if (empty($errors)) {
    drush_log('DB checks completed. No problems were found.', 'success');
  }
  else {
    drush_log("\nThe following issues were found with this site:", 'error');
    foreach ($errors as $key => $value) {
      drush_log('- ' . $value, 'error');
    }
  }
}

// Check if stage file proxy isn't enabled.
$sfp_status_query = db_select('system', 's')
  ->fields('s', ['name', 'status'])
  ->condition('s.name', 'stage_file_proxy', '=')
  ->execute()
  ->fetchAssoc();

if ($sfp_status_query['status'] === 1) {
  $errors['dblog_enabled'] = 'Stage file proxy module is still enabled.';
}

// Check if database logging isn't enabled.
$dblog_status_query = db_select('system', 's')
  ->fields('s', ['name', 'status'])
  ->condition('s.name', 'dblog', '=')
  ->execute()
  ->fetchAssoc();

if ($dblog_status_query['status'] === 1) {
  $errors['dblog_enabled'] = 'Database logging is still enabled. This will cause unnecessary read and write queries.';
}

// Make sure 'devel' module isn't enabled.
$devel_status_query = db_select('system', 's')
  ->fields('s', ['name', 'status'])
  ->condition('s.name', 'devel', '=')
  ->execute()
  ->fetchAssoc();

if ($devel_status_query['status'] === 1) {
  $errors['devel_module_enabled'] = 'Devel module is still enabled.';
}

// Check User ID 1 is blocked.
$user_status_query = db_select('users', 'u')
  ->fields('u', ['uid', 'status'])
  ->condition('u.uid', 1, '=')
  ->execute()
  ->fetchAssoc();

if ($user_status_query['status'] === 1) {
  $errors['user_id_1_enabled'] = 'User ID 1 is still enabled. This account should be blocked for security reasons.';
}

// PHP filter should not be enabled on any site.
$php_filter_status_query = db_select('filter_format', 'f')
  ->fields('f', ['format', 'status'])
  ->condition('f.format', 'php_code', '=')
  ->execute()
  ->fetchAssoc();

if ($php_filter_status_query['status'] === 1) {
  $errors['php_filter_enabled'] = 'The PHP filter is still enabled and could cause potential security issues.';
}

drush my-module-run-db-checks

/**
 * Implements drush_command().
 */
function my_module_drush_command() {
  $items = [];
  $items['my-module-cc-cache-bin'] = [
    'description' => 'Clear a specific cache bin.',
    'callback' => 'my_module_cc_cache_bin',
    'examples' => [
      'drush my-module-cc-cb cid_you_want_to_clear cache_table' => 'Clear passed cid from passed table.',
    ],
    'arguments' => [
      'cid' => dt('CID for items to clear'),
      'cache_bin'   => dt('A required cache bin argument.'),
      'wildcard' => dt('Whether to do a wildcard delete'),
    ],
    'aliases' => ['my-module-cc-cb'],
  ];

  return $items;
}

/**
 * Exposes cache_clear_all to drush for deploy hooks.
 *
 * @param string|string[] $cid
 *   Cache id or array of cache ids to clear.
 * @param string $bin
 *   The bin name to clear.
 * @param bool $wildcard
 *   Default false, whether to use wildcard matching.
 */
function my_module_cc_cache_bin($cid, $bin, $wildcard = FALSE) {
  cache_clear_all($cid, $bin, $wildcard);
  drush_log('Cleared cids: ' . $cid . ' in bin: ' . $bin, 'ok');
}

drush my-module-cc-cb cid_you_want_to_clear cache_table

/**
 * Rebuilding theme data properly.
 */
function my_module_rebuild_theme() {
  system_rebuild_theme_data();
  drush_log('Theme data rebuilt.', 'ok');
}