Build an app for Volusion.com

We would like to build a payment's gateway app for Volusion platform ([login to view URL]) that will make checkouts using our paybar as a payment option. Here is the info about our Paybar tool: [login to view URL] [login to view URL] [login to view URL] Here is an example of app: [login to view URL] All data from the cart will be send via API to servers and send response back. This task will include, the plugin(the files), documentation, screenshots and testing (exactly like here: [login to view URL]). Xsolla provides dynamic payment solutions to cart owners. For example, user gets to checkout page, is able to select their payment option of choice for example, credit card, paypal, or Xsolla's payment methods. Xsolla's front end will load 3 to 5 dynamic options that wil allow the user to complete a payment and be returned to the store with a completed payment. Requirements You must be an expert on this e-commerce platform and have completed previous plugins before. Please send examples.