code: protected function loadConfigFiles()
      {
          try {
              if (file_exists($this->cachePath('config.php'))) {
                  $this->config = require $this->cachePath('config.php');
              } else {
                  $dotenv = new \Dotenv\Dotenv($this->root);
                  $dotenv->load();
                  foreach (glob($this->root . '/config/*.php') as $file) {
                      $keyName = strtolower(str_replace(
                          [$this->root . '/config/', '.php'], '', $file
                      ));
                      $this->config[$keyName] = require $file;
                  }
              }
          } catch (Exception $e) {
              die(printf(
                  "Configuration information could not be retrieved properly.\nError Message: %s",
                  $e->getMessage()
              ));
          }
      }
docs: Load application configuration files
  
  @return void
  @throws