What is your experience developing in pure PHP without using third-party frameworks?

Development experience with pure PHP without frameworks includes creating web applications using the basic features of the language: handling HTTP requests, working with sessions, connecting to a database via PDO or mysqli, and implementing a manually crafted MVC-like architecture. For example, you can write a simple router in PHP that parses the URL and calls the corresponding function:

<?php
// Example of simple routing
$request = $_SERVER['REQUEST_URI'];

if ($request === '/home') {
    echo 'Home Page';
} elseif ($request === '/about') {
    echo 'About Us';
} else {
    http_response_code(404);
    echo 'Page Not Found';
}

This approach requires careful management of security, data validation, and code organization, as there are no ready-made framework tools.