WebPay is payment gateway service in Japan. See also https://webpay.jp/.

PingPlusPlus is the easiest way to accept payments online. See https://pingxx.com for details.

Gem using curl to post to Venmo payment gateway

Adds Purchase Order as a Payment Method to Spree Commerce

Our APIs allow easy and secure access to bank account data and payment initiation. The account data accessible are account holder's personal information, account balances, transaction history and much more. The available payment methods depend on the banks implementation but typically are domesti...

Validation for Dutch bank account numbers, Citizen Service Numbers (BSN) and Payment reference

Provides an interface to AzeriCard online payment processing system

Paysera.com payment API

An engine for the Straight payment gateway software. Requires no state to be saved (that is, no storage or DB). Its responsibilities only include processing data coming from an actual gateway.

M-Pesa SDK for Ruby is an unofficial library aiming to help businesses integrating every M-Pesa operations to their Ruby applications.

SystemPay is a gem to ease credit card payment with Natixis Paiements / CyberplusPaiement bank system. It's a Ruby on Rails port of the connexion kits published by the bank.

Instamojo Ruby library - Assists you to programmatically create, edit and delete offers on Instamojo. Also supports listing, updation and details of Payments, Payments Requests and Refunds.

Add support to ActiveMerchant for the Sermepa payment gateway by Servired used by many banks in Spain

Add Ogone payments functionality to your Rails application

Integration with PayTrace Payment Gateway

This gem allows your Ruby (1.9.2+) or Rails (3.2+) app to quickly integrate with Culqi Payment processor. It handles Culqi's flavor of encryption, decryption and Culqi ticket creation.

Qiwi payments solution

Gem for use Sofort Api in Ruby. Payments and check details. SOFORT Überweisung - Sofort Api Banking

Gem for integration CSOB PaymentGateway in Ruby

Ruby client library for integrating with Affirm financing payments