Perfex CRM to ShipStation API Integration

I need a custom module to sync orders from Perfex CRM to ShipStation via API. The entire order details need to be transferred, including:

- Customer name and address
- Customer phone and email
- Order number and items

Additionally, after processing, ShipStation should return the following data to Perfex CRM:

- Carrier information (preferably USPS)
- Tracking number
- Shipping cost

The integration should be coded within a module using existing database tables.

Ideal skills and experience include:
- Experience with Perfex CRM
- Proficient in API integration
- Strong coding skills, preferably in PHP
- Familiarity with ShipStation and shipping logistics