I am running Drupal 8 with Commerce 2.
I have a flat-rate shipping option set up for multiple regions and I now need to increase the shipping costs under certain circumstances, eg.:
- Order contains a specific product but not another specific product
- Order contains a product from any category except a specific one
- Order contains products from a certain category totaling over price x
The "rules" in the shipping method itself are simply not enough to fit my needs.
How would I go about implementing such custom shipping rules?