BLOCK OPEN SOURCE
At Block, we believe open source is at the heart of innovation and community empowerment. Our vision is to nurture a diverse and vibrant open source ecosystem that removes barriers to technology and fosters economic opportunities for all.
By collaborating in the open, we create higher quality software, hardware, and protocols through relentless collective examination, and also ensure our systems, hardware, and protocols evolve to meet real-world needs.
We are committed to building solutions that serve our customers, while enriching the broader developer community with open, accessible tools. Our open source strategy emphasizes transparency, collaboration, and shared progress—because building together empowers everyone.
OkHttp is a modern HTTP client designed for efficiency and reliability, ensuring faster load times and reduced bandwidth usage. It supports HTTP/2 to allow multiple requests to share a single connection, uses connection pooling to reduce latency, and leverages features like transparent GZIP compression to shrink downloads and response caching to eliminate redundant network requests. With built-in resilience, OkHttp can recover from common network issues and seamlessly handle services with multiple IP addresses, ensuring robust connectivity across IPv4, IPv6, and redundant data centers. It also supports advanced TLS features, including TLS 1.3, ALPN, and certificate pinning, for secure communication.
Built with developers in mind, OkHttp offers an easy-to-use request/response API with fluent builders and immutability. It supports both synchronous and asynchronous calls, providing flexibility for different use cases. Whether for handling basic requests or navigating complex network conditions, OkHttp simplifies HTTP communication while maintaining high performance and reliability. OkHttp is also the default HTTP client for Android, and is popular in both client and server side development.
Retrofit is a type-safe HTTP client for Java and Android that simplifies API integration by turning RESTful APIs into easy-to-use Java interfaces. It handles all the complexities of network calls, including URL creation, request execution, and response parsing, enabling developers to focus on building features. Retrofit integrates seamlessly with OkHttp for efficient HTTP communication and Gson or Moshi for JSON serialization.
Designed for flexibility and ease of use, Retrofit supports synchronous and asynchronous requests, ensuring compatibility with various application architectures. It also allows customization through annotations for headers, query parameters, and request bodies. With Retrofit, developers can quickly implement reliable, scalable API interactions, reducing boilerplate code and enhancing productivity.
The Lightning Development Kit (LDK) is a flexible, modular library designed to help developers integrate Lightning Network functionality into their applications with ease. It provides core Lightning Network capabilities such as channel management, routing, and transaction signing while giving developers full control over their application’s design and features. LDK supports integration with custom wallets, storage solutions, and networking stacks, ensuring adaptability to diverse use cases.
Built for scalability and security, LDK is written in Rust, offering strong safety guarantees and performance. Its modular architecture allows developers to pick and choose the components they need, enabling seamless integration into existing systems. By empowering developers to build with the Lightning Network, LDK advances Bitcoin adoption and fosters innovation in decentralized financial applications.
Block has a variety of open source projects across our brands. From payment systems to privacy initiatives, from cloud infrastructure to bitcoin hardware wallets, from AI agent frameworks to music streaming, our projects span diverse fields, and each one is open for contributions and collaboration. Visit our GitHub organizations and project pages to learn more.
Whether you're interested in financial services, cryptography, blockchain, AI, or developer tools, there's a project for you to get involved in.
BLOCK OPEN SOURCE
At Block, we believe open source is at the heart of innovation and community empowerment. Our vision is to nurture a diverse and vibrant open source ecosystem that removes barriers to technology and fosters economic opportunities for all.
By collaborating in the open, we create higher quality software, hardware, and protocols through relentless collective examination, and also ensure our systems, hardware, and protocols evolve to meet real-world needs.
We are committed to building solutions that serve our customers, while enriching the broader developer community with open, accessible tools. Our open source strategy emphasizes transparency, collaboration, and shared progress—because building together empowers everyone.
OkHttp is a modern HTTP client designed for efficiency and reliability, ensuring faster load times and reduced bandwidth usage. It supports HTTP/2 to allow multiple requests to share a single connection, uses connection pooling to reduce latency, and leverages features like transparent GZIP compression to shrink downloads and response caching to eliminate redundant network requests. With built-in resilience, OkHttp can recover from common network issues and seamlessly handle services with multiple IP addresses, ensuring robust connectivity across IPv4, IPv6, and redundant data centers. It also supports advanced TLS features, including TLS 1.3, ALPN, and certificate pinning, for secure communication.
Built with developers in mind, OkHttp offers an easy-to-use request/response API with fluent builders and immutability. It supports both synchronous and asynchronous calls, providing flexibility for different use cases. Whether for handling basic requests or navigating complex network conditions, OkHttp simplifies HTTP communication while maintaining high performance and reliability. OkHttp is also the default HTTP client for Android, and is popular in both client and server side development.
Retrofit is a type-safe HTTP client for Java and Android that simplifies API integration by turning RESTful APIs into easy-to-use Java interfaces. It handles all the complexities of network calls, including URL creation, request execution, and response parsing, enabling developers to focus on building features. Retrofit integrates seamlessly with OkHttp for efficient HTTP communication and Gson or Moshi for JSON serialization.
Designed for flexibility and ease of use, Retrofit supports synchronous and asynchronous requests, ensuring compatibility with various application architectures. It also allows customization through annotations for headers, query parameters, and request bodies. With Retrofit, developers can quickly implement reliable, scalable API interactions, reducing boilerplate code and enhancing productivity.
The Lightning Development Kit (LDK) is a flexible, modular library designed to help developers integrate Lightning Network functionality into their applications with ease. It provides core Lightning Network capabilities such as channel management, routing, and transaction signing while giving developers full control over their application’s design and features. LDK supports integration with custom wallets, storage solutions, and networking stacks, ensuring adaptability to diverse use cases.
Built for scalability and security, LDK is written in Rust, offering strong safety guarantees and performance. Its modular architecture allows developers to pick and choose the components they need, enabling seamless integration into existing systems. By empowering developers to build with the Lightning Network, LDK advances Bitcoin adoption and fosters innovation in decentralized financial applications.
Block has a variety of open source projects across our brands. From payment systems to privacy initiatives, from cloud infrastructure to bitcoin hardware wallets, from AI agent frameworks to music streaming, our projects span diverse fields, and each one is open for contributions and collaboration. Visit our GitHub organizations and project pages to learn more.
Whether you're interested in financial services, cryptography, blockchain, AI, or developer tools, there's a project for you to get involved in.
We highly encourage you to join us in our work. Each project comes with a contribution guide, which has details on how to communicate with contributors and maintainers of that project, including best practices for filing bugs, requesting features, or brainstorming on ideas.
In addition, Block Open Source also runs a Discord server, where you can get in touch with the Block Open Source team. Drop in and say hello!
We care deeply about fostering a safe, inclusive, and productive open source community. We want every contributor to feel welcome and confident in collaborating with us, whether you’re fixing a typo or proposing a new feature. Here are the principles and policies that guide our work:
Block proudly sponsors and collaborates with numerous foundations that are pushing technology forward. Our involvement is rooted in our belief that the open source community thrives when we invest in collective progress. We contribute to the sustainability and growth of open technologies by supporting:
We highly encourage you to join us in our work. Each project comes with a contribution guide, which has details on how to communicate with contributors and maintainers of that project, including best practices for filing bugs, requesting features, or brainstorming on ideas.
In addition, Block Open Source also runs a Discord server, where you can get in touch with the Block Open Source team. Drop in and say hello!
We care deeply about fostering a safe, inclusive, and productive open source community. We want every contributor to feel welcome and confident in collaborating with us, whether you’re fixing a typo or proposing a new feature. Here are the principles and policies that guide our work:
Block proudly sponsors and collaborates with numerous foundations that are pushing technology forward. Our involvement is rooted in our belief that the open source community thrives when we invest in collective progress. We contribute to the sustainability and growth of open technologies by supporting: