Vingd API enables you to use Vingd to sell items, reward users and create vingd vouchers at your own site.
To use vingd production one should open vingd business account (send email to firstname.lastname@example.org) and configure API to use vingd production endpoint and frontend.
The "formally inclined" are encouraged to take a look at the Vingd purchase sequence diagram here.
Vingd can optionally be used in popup mode for quick tasks like buying items, using vouchers and checking account balance (and also for authentication if vingd oauth is used).
Full source code is available here. Minimized JS files are also available on Vingd CDN (main.min.js and popup.min.js) and can be directly linked to (good for keeping up to date). For a quick start follow a how-to guide given in the docs.