You can set the shipping cost in 2 ways: a simple flat shipping charge, or write your own advanced shipping calculator.

Simple Flat Charge

Simply set the amount in the config like so:

// default shipping amount
'shipping' => [
    'calculator' => null,
    'cost' => 12,

Remember to set 'calculator' to null.

Advanced Shipping Calculator

If you need more control on how to set the shipping cost, you can write your own ShippingCalculator class!

Just set the class in the config like so:

'shipping' => [
    'calculator' => ExampleShippingCalculator::class,

This class only needs to implement 1 method:

class ExampleShippingCalculator
    public static function calculate(Order $order)
        $charge = 24 // perform your logic
        return $charge * 100;

This method will be passed the Order as a parameter. You should return the charge in cents.

See the included ExampleShippingCalculator for inspiration.