How do I add a custom Doctrine data type to SlimPHP Framwork?

Question

I found a class that adds custom type to Doctrine annotation (TINYINT):

<?php

namespace AppBundle\Doctrine\DBAL\Types;

use Doctrine\DBAL\Types\Type;
use Doctrine\DBAL\Platforms\AbstractPlatform;

class Tinyint extends Type
{
    const TINYINT = 'tinyint';

    public function getSQLDeclaration(array $fieldDeclaration, AbstractPlatform $platform)
    {
        $fieldDeclaration = array_merge([
            'length' => 1,
        ], $fieldDeclaration);

        return sprintf("TINYINT(%d)",
                $fieldDeclaration['length']
            );
    }

    public function convertToPHPValue($value, AbstractPlatform $platform)
    {
        return (int) $value;
    }

    public function convertToDatabaseValue($value, AbstractPlatform $platform)
    {
        return (int) $value;
    }

    public function getName()
    {
        return self::TINYINT;
    }

    public function getBindingType()
    {
        return \PDO::PARAM_INT;
    }
}

But there's only an example of how to add it to Symfony. I need to do this using the SlimPHP Framework...

Maybe someone else has had the same experience!?