7 Best Open-source Payment Gateway/Processing Tools

Hyperswitch is an advanced payment orchestration platform designed to improve payment authorization rates and reduce processing latency. By intelligently routing transactions to the most suitable payment service providers (PSPs), Hyperswitch can achieve up to a 10% increase in successful authorizations. This system ensures that businesses can maximize their revenue potential by connecting directly with bank acquirers across various markets.

1. E-commerce platforms: Optimize payment processes to increase conversion rates.
2. Subscription services: Enhance recurring billing efficiency with improved authorizations.
3. Marketplaces: Manage complex payment flows between buyers and sellers effectively.

Kill Bill is an open-source billing and payment solution designed to cater to businesses of all sizes, from startups to large enterprises. It provides a comprehensive framework for managing subscriptions, payments, and financial reporting, allowing organizations to scale their billing infrastructure efficiently. With its robust partner ecosystem, Kill Bill integrates seamlessly with various payment gateways and fraud prevention tools, ensuring a versatile and secure payment experience.

1. SaaS companies: Efficiently manage recurring billing and subscription models.
2. E-commerce platforms: Handle diverse payment methods and customer transactions smoothly.
3. Membership organizations: Streamline billing processes for recurring memberships and donations.

Polar is a merchant of record platform that enables businesses to manage their payments seamlessly, handling everything from billing to international taxes. By automating complex payment processes, Polar allows developers and organizations to focus on their core operations without the hassle of financial administration. Its user-friendly interface and built-in analytics dashboard provide valuable insights into sales performance and customer engagement.

1. SaaS businesses: Simplify subscription billing and manage customer payments efficiently.
2. E-commerce platforms: Handle transactions smoothly while managing taxes automatically.
3. Digital service providers: Streamline payment processing for online services or applications.

UniBee is an open-source subscription management system designed to simplify billing and invoicing for businesses of all sizes. It offers a variety of customizable billing models, including recurring, one-time, and usage-based options, allowing organizations to tailor their payment structures to meet specific needs. With its user-friendly interface, UniBee enables businesses to manage their global audience efficiently through a single billing system.

1. SaaS companies: Efficiently manage subscription billing and customer invoicing.
2. E-commerce platforms: Handle diverse payment methods and global transactions.
3. Digital service providers: Simplify billing processes for online services.

Omnipay is a robust payment processing library specifically designed for PHP, enabling developers to interact with various payment gateways through a unified interface. Inspired by Active Merchant, Omnipay provides a clear and consistent API that allows for easy switching between different payment providers without the need to rewrite code. This flexibility is particularly beneficial for projects that require support for multiple gateways.

1. E-commerce platforms: Facilitate payments across various online stores.
2. Subscription services: Manage recurring billing with multiple gateways.
3. Custom shopping carts: Build tailored solutions that require diverse payment options.

Payum is an open-source payment processing library designed for PHP developers, enabling seamless integration with various payment gateways. It offers a unified API that simplifies the handling of complex payment processes, allowing developers to focus on building their applications rather than dealing with the intricacies of individual payment providers. Payum supports a wide range of gateways, making it versatile for different business needs.

1. E-commerce websites: Facilitate payments across various online stores.
2. Subscription services: Manage recurring billing and customer payments efficiently.
3. Custom applications: Build tailored solutions requiring diverse payment options.

ActiveMerchant is a widely used Ruby library that provides a straightforward way to integrate payment processing into applications. Designed to work with various payment gateways, ActiveMerchant offers a unified interface that allows developers to handle transactions without needing to learn the specifics of each gateway. This flexibility makes it an ideal choice for developers looking to implement payment solutions quickly and efficiently.

1. E-commerce platforms: Facilitate payments across various online stores and services.
2. Subscription services: Efficiently manage recurring billing for digital products.
3. Custom applications: Build tailored solutions that require diverse payment options.