Custom Third Party Carrier Calculated Rates

[Chris_Sydney]

Hey All, 

I am wondering if anyone has built their own 3rd party carrier rates module to provide custom rates?

My current limitation with the Shopify zoning is that I cant control Postcodes, whilst I can use another service, given Carrier Calculated rates are just pulling from a JSON response, I wondering if someone has gone about building their own rates, and if so could you share guidance on it?