How can I solve "laravel/horizon v1.1.0 requires ext-pcntl * -> the requested PHP extension pcntl is missing from your system"?

Question

Run composer with the --ignore-platform-reqs option and specify pcntl and posix

composer install --ignore-platform-reqs

As per the accepted answer, but you can add this to your composer.json so that you don't have to run --ignore-platform-reqs all the time

"config": {
  "platform": {
    "ext-pcntl": "8.0",
    "ext-posix": "8.0"
  }
}

install horizon this way :

composer require laravel/horizon --ignore-platform-reqs

then run

php artisan horizon:install

pcntl extension is not supported on Windows. (based on your XAMPP information)

Please see these github issues on laravel/horizon page #131, #78.

I suggest you use Laravel Homestead on your Windows system, It is easy to setup and will save you from many of the similar problems in future.

If you are using docker based on a Unix image you can add it with the docker utility:

docker-php-ext-install pcntl

You can then confirm that this extension is installed and enabled inside of your container:

?> php -i | grep pcntl
/usr/local/etc/php/conf.d/docker-php-ext-pcntl.ini,
pcntl
pcntl support => enabled