Widget-based integration of payment gateway functionality into transactional sites

A computer-implemented method implemented by a computing system of a payment service, the computer-implemented method comprising:

• generating code for parsing by a client device, wherein the code, when parsed by the client device during display of a merchant web page, causes the client device, without being redirected to a web site of the payment service or otherwise navigating away from the merchant web page, to add one or more input elements to the merchant web page enabling a user to input information related to payment for a transaction and submit the information to the payment service, wherein the code allows the user to interact with the payment service directly from the merchant web page to cause the transaction to be executed to completion, and without displaying to the user any indication that the payment is being processed by a party other than the merchant;
• receiving, during display of merchant web page at the client device, a request from the client device for the code;
• and
• transmitting the code to the client device for parsing during display of the merchant web page.

A system comprising:

• a physical data store including code parseable by a client device during display of a merchant web page, wherein the code, when parsed by the client device, causes the client device, without being redirected to a web site of the payment service or otherwise navigating away from the merchant web page, to add one or more input elements to the merchant web page enabling a user to input information related to payment for a transaction and submit the information to the payment service, wherein the code allows the user to interact with the payment service directly from the merchant web page to cause the transaction to be executed to completion, and without displaying to the user any indication that the payment is being processed by a party other than the merchant;
• and
• one or more computing devices configured with computer-executable instructions to:
• receive, during display of merchant web page at the client device, a request from the client device for the code;
• and
• transmit the code to the client device for parsing during display of the merchant web page.

Non-transitory computer-readable media comprising:

• first code parseable by a client device during display of a merchant web page, wherein the code, when parsed by the client device, causes the client device, without being redirected to a web site of the payment service or otherwise navigating away from the merchant web page, to add one or more input elements to the merchant web page enabling a user to input information related to payment for a transaction and submit the information to a payment service, wherein the code allows the user to interact with the payment service directly from the merchant web page to cause the transaction to be executed to completion, and without displaying to the user any indication that the payment is being processed by a party other than the merchant;
• and
• second code executable by one or more physical computing devices of the payment service to:
• receive, during display of merchant web page at the client device, a request from the client device for the first code;
• and
• transmit the first code to the client device for parsing during display of the merchant web page.