What APIs should I call to integrate

Hi all,

Our company is an e-commerce site selling furniture both online & offline. We use Salesforce to manage our customer base and Magento as e-commerce platform. Now we intend to move from Magento to OpenCart as Magento is too slow and buggy.

That's why we also intend to develop an in-house integration between OpenCart & Salesforce by our own. We want it to be something looks like the tool we are using now: magento salesforce integration. It will save us so much time when we can integrate data between the 2 systems (OpenCart & Salesforce). Some mapping fields we have finalized:
+ Name
+ SKUs
+ Email
+ Shipping Address
About 7 mapping fields more we are discussing. Can you show me what APIs can I call to develop the integration tool?

You can also visit this topic: http://forum.opencart.com/viewtopic.php?f=23&t=164071

I am thinking of integrating opencart to my website www.leksmediaconcept.com without service disruption, whats the best way to go about it?