Strict types sadness demo.

Driver.php

<?php

interface Driver {
    public function set(callable $callback);
    public function invoke($foo);
}
<?php

class DriverA implements Driver {
    private $callback;

    public function set(callable $callback) {
        $this->callback = $callback;
    }
    
    public function invoke($foo) {
        ($this->callback)($foo);
    }
}

DriverA.php

<?php

class DriverA implements Driver {
    private $callback;

    public function set(callable $callback) {
        $this->callback = $callback;
    }
    
    public function invoke($foo) {
        ($this->callback)($foo);
    }
}

DriverB.php

<?php

declare(strict_types=1);

class DriverB implements Driver {
    private $callback;

    public function set(callable $callback) {
        $this->callback = $callback;
    }

    public function invoke($foo) {
        ($this->callback)($foo);
    }
}

test.php

<?php

require __DIR__ . "/Driver.php";
require __DIR__ . "/DriverA.php";
require __DIR__ . "/DriverB.php";

$driverA = new DriverA;
$driverB = new DriverB;

$callback = function (string $foo) {

};

$driverA->set($callback);
$driverB->set($callback);

$driverA->invoke(42);
$driverB->invoke(42);

// Results in

// PHP Fatal error:  Uncaught TypeError: Argument 1 passed to {closure}() must be of the type string, integer given, called in /tmp/DriverB.php on line 13 and defined in /tmp/test.php:10
// Stack trace:
// #0 /tmp/DriverB.php(13): {closure}(42)
// #1 /tmp/test.php(18): DriverB->invoke(42)
// #2 {main}
//   thrown in /tmp/test.php on line 10