Official Node.js SDK for the Authorize.Net payments platform
the module requires NodeJS version 4.8.4 or higher and is hosted on Github and
NPM. To get started using this SDK, it's highly recommended to download Authorize.net sample code repository from https://github.com/AuthorizeNet/sample-code-node but if you want to use NPM directly you should use the instructions on https://www.npmjs.com/package/authorizenet the official NPM module for authorize.net
The extension is provided by Authorize.net and is Free