Shopify shipping integration

We are looking for someone with good portfolio in Shopify Apps to integrate our courier service.
Tasks:
- Add a form to insert warehouses in DB and standard parcels per warehouse (2 CRUDs)
- Add a drop down in product adding form to select from which warehouse the product is leaving
- Add parcel dimensions in product adding form (multiple parcels with: width, height, depth, weight, weight unit measure)
- Add a form to insert types of parcels in admin
- Add a dropdown to category add/edit page to select what type of parcels are in that category
- Integrate with our shipping platform through API to get price at checkout, place order, get AWB link for tracking for customer
- Check every 15 min our API for AWB updates to update order status in Shopify.

API is already written, we have senior coders which can help with any questions you might have. We only want integration into our API.
Main tasks are:
- Warehouses
- Standard parcels per warehouse
- Product adding form edited with required new fields
- Category adding form edited with required new fields.