What are some recommended PHP frameworks or components, like Symfony or Slim, that can streamline the development process while maintaining flexibility for smaller projects?

When working on smaller PHP projects, it's important to choose frameworks or components that can streamline the development process without sacrificing flexibility. Symfony and Slim are two popular options that offer a good balance between structure and customization for smaller projects.

// Example using Slim framework
require 'vendor/autoload.php';

$app = new \Slim\App();

$app->get('/', function ($request, $response, $args) {
    $response->getBody()->write("Hello, world!");
    return $response;
});

$app->run();