The PayPal Adaptive Payments Ruby SDK by PayPal allows developers to integrate the PayPal Adaptive Payments API into their Ruby projects and applications. Example code and a sample app are provided in the documentation.
Bitpay's API allows for businesses and employees to accept BitCoin for their services and goods. Now with the addition of Newegg to it's repertoire of business affiliates, BitPay is receiving more credence as a leader in the march toward the legitimization of BitCoin as a secure digital payment system.
This week Google announced support of three new APIs in it's upcoming beta release of Chrome 61. These APIs, integrated from existing W3C standards, include the Payment Request API for making payment checkouts easier, the Web Share API for implementing native sharing capabilities and the WebUSB API.