TechPrufer
Get started
Cloudflare
Cloudflare logoCloudflare · Feature trail

Open Source Software & Community Contributions

25 posts · Oct 2013 – Mar 2025

What this trail covers

Cloudflare has a deep and reciprocal relationship with the open source community. Initially, the company relied heavily on open source software for its core infrastructure, including nginx and PostgreSQL. This evolved into actively contributing back to these projects, releasing their own open source tools and libraries, such as Red October, Lua Resty Shcache, Lua Resty Core, Go Libs, BM, Lua Raven, Lua Resty Logger Socket, conf, Lua Resty Kyoto Tycoon, Go LZ4, Aho Corasick, kt-fdw, Lua Resty Coo. This post details the company's philosophy of open-sourcing components and contributing to external projects, highlighting specific examples of contributions and sponsored work.

All Cloudflare trails
  1. New URLPattern API brings improved pattern matching to Node.js and Cloudflare WorkersThis post details Cloudflare's contribution of a URLPattern API implementation to Node.js, leveraging their high-performance Ada URL parser. This effort aims to standardize URL pattern matching across JavaScript runtimes like Node.js and Cloudflare Workers, reinforcing Cloudflare's commitment to open-source contributions and web interoperability. The post also highlights the importance of the URLPattern API for routing and its inclusion in the WinterTC Minimum Common API.
  2. Open source all the way down: Upgrading our developer documentationThis post details a significant evolution in Cloudflare's open source engagement by treating developer documentation as an open source product. It describes the migration of the documentation site's framework from Hugo to Astro and Starlight, highlighting the benefits of enhanced content organization, extensibility, improved development experience, and better JavaScript/TypeScript support. The post also details the technical migration process using Abstract Syntax Trees (ASTs) and quantifies the effort, emphasizing the success of the migration with community MVP involvement and no downtime.
  3. polyfill.io now available on cdnjs: reduce your supply chain riskThis post details Cloudflare's contribution to the open-source polyfill.io project by providing an alternative endpoint on cdnjs. This initiative addresses supply chain risks associated with the original polyfill.io domain by leveraging Cloudflare's infrastructure and reputation. Furthermore, Cloudflare has forked polyfill.io to run on Cloudflare Workers, utilizing Rust and D1 for storage, showcasing their commitment to supporting and enhancing open-source projects.
  4. Open sourcing Pingora: our Rust framework for building programmable network servicesThis post announces the open-sourcing of Pingora, a Rust framework developed by Cloudflare for building programmable network services, particularly HTTP proxy services. It highlights Pingora's memory safety, performance benefits, and customizability, making it suitable for security-sensitive and performance-critical applications. The post details Pingora's capabilities, including support for HTTP/1, HTTP/2, TLS, and TCP, along with customizable load balancing and graceful upgrades. It also provides a practical example of building a load balancer with Pingora and discusses future plans and contribution guidelines.
  5. Open sourcing our fork of PgBouncerThis post details Cloudflare's contribution to the open source community by open-sourcing their fork of PgBouncer. This fork includes fixes for an authentication bug affecting HBA authentication and new features for enforcing per-user and per-pool connection limits at runtime, which are crucial for tenant performance isolation in their Postgres infrastructure. They have also made administrative commands available to dynamically adjust these limits.
  7. Cloudflare’s Partnership with HashiCorp and Bootstrapping Terraform with Cf-TerraformingThis post details the evolution of Cloudflare's partnership with HashiCorp, focusing on the development and improvement of the Cloudflare Terraform provider and the `cf-terraforming` tool. It highlights how customer demand drove Cloudflare to take over support for the Terraform provider, leading to its verification. The post also explains the challenges and lessons learned in maintaining `cf-terraforming`, particularly regarding API changes and Terraform updates, and introduces a new, simplified version that leverages Terraform's schema and `terraform-exec` for easier resource management and bootstrapping of existing Cloudflare configurations into an infrastructure-as-code workflow.
  8. Cloudflare Repositories FTWThis post details how Cloudflare's CDN and large file caching capabilities were leveraged by the Kali Linux project to significantly improve their download infrastructure. It highlights the challenges of distributing large ISO images and apt repositories, the initial skepticism and subsequent successful integration with Cloudflare's services, and the resulting substantial bandwidth savings and performance improvements for the Kali community. This demonstrates Cloudflare's commitment to supporting open source projects with its core infrastructure.
  9. Introducing Cf-TerraformingThis post introduces `cf-terraforming`, a new open-source utility that allows users to export their existing Cloudflare configurations (defined via the dashboard and API) into Terraform-compliant configuration files. This tool simplifies the migration of complex Cloudflare setups to infrastructure-as-code, demonstrating Cloudflare's commitment to supporting and enhancing the open-source ecosystem by providing tools that integrate with popular open-source solutions like Terraform.
  10. Porting Our Software to ARM64This post details the technical challenges and solutions involved in porting Cloudflare's internal software stack to the ARM64 architecture. It highlights the use of open-source tools and community efforts in supporting ARM64, and the development of custom emulation and cross-compilation strategies using QEMU and Docker to achieve software parity across different hardware architectures. The post also discusses specific technical hurdles encountered with languages like Go and the solutions implemented, such as CPU pinning for threading issues and the use of `--rpath` for shared library management.
  11. Helping to make LuaJIT fasterThis post details Cloudflare's funding of an academic research group at King's College London to improve the performance of LuaJIT, a critical component of Cloudflare's infrastructure. It highlights Cloudflare's commitment to giving back to the open-source community by supporting research that benefits the broader LuaJIT ecosystem, with all improvements being open-sourced.
  12. A New API Binding: cloudflare-phpThis post announces the release of an official PHP binding for the Cloudflare API (cloudflare-php). It highlights the design decisions made, including the exclusive use of PHP 7 for modern features like scalar type hinting and return type declarations, and the adoption of object composition and dependency injection for flexibility and maintainability. The post also details how the binding facilitates testing through adherence to PSR-7 standards and the use of mocking.
  13. Generating Documentation for TypeScript ProjectsThis post introduces the use of TypeScript for generating documentation, highlighting its advantages over JSDoc by providing compile-time error checking and tightly coupled documentation. It details the adoption and use of TypeDoc at Cloudflare for automated documentation generation and discusses how to extend this beyond API references to create more dynamic and linked documentation. The post also announces plans to open-source the documentation generation tools and themes developed by Cloudflare, further contributing to the open-source ecosystem.
  14. CloudFlare's JSON-powered Documentation GeneratorThis post introduces and open-sources a comprehensive toolchain for generating API documentation from JSON Schemas. It details the individual components (json-schema-loader, json-schema-example-loader, doca-bootstrap-theme, doca) and the underlying technologies (Webpack, Handlebars.js, React) used to create a modular, extensible, and performant documentation generation system. This contributes to Cloudflare's open-source efforts by providing a valuable tool for developers and showcasing their internal engineering practices.
  15. Open Sourcing CloudFlare’s UI FrameworkThis post details Cloudflare's decision to open-source its internal UI framework, cf-ui, which was rebuilt from Backbone & Marionette to React & Redux. It highlights the use of Lerna for managing a multi-package repository, the development of 'builder' components for easier Redux integration, integrated test utilities, a strategy of wrapping APIs for flexibility, and improvements made to component accessibility, including open-sourcing related libraries. This contribution directly aligns with Cloudflare's commitment to the open source community and sharing technical advancements.
  16. Building the simplest Go static analysis toolThis post details the creation and open-sourcing of `vendorcheck`, a simple static analysis tool for Go. It highlights Cloudflare's proactive approach to improving developer tooling within the Go ecosystem by addressing a specific pain point related to Go's vendoring mechanism. The post also serves as a recruitment tool, indicating the team's engagement with Go development and their willingness to contribute to open source.
  17. Introducing CFSSL 1.2This post introduces CFSSL 1.2, detailing new features like a TLS endpoint scanner for evaluating server security configurations, a Transport package for Go developers to simplify encrypted connections (handling key management, certificate issuance, and renewal), and enhanced revocation support with PostgreSQL backend, CRL, and OCSP. It also highlights the motivation behind treating internal networks as hostile and the use of CFSSL for service-to-service encryption and mutual authentication.
  18. Single RX queue kernel bypass in Netmap for high packet rate networkingThis post details Cloudflare's contribution to the Netmap project by developing and proposing a 'single RX queue mode'. This enhancement allows user-space applications to bypass the Linux kernel for specific network flows, enabling high-throughput packet processing for handling large packet floods, particularly on Intel IXGBE NICs where direct kernel bypass was not previously available. The post also outlines the technical implementation, configuration, and performance benefits of this contribution, highlighting its value to the open-source community.
  19. Fighting Cancer: The Unexpected Benefit Of Open Sourcing Our CodeThis post details Cloudflare's optimized fork of the zlib compression library, highlighting its performance improvements over the original and other forks. It showcases the library's use in critical scientific research (cancer research via DNA sequencing) as an unexpected benefit of open-sourcing, reinforcing Cloudflare's commitment to contributing to the open-source community and the broad impact of their code.
  20. Kyoto Tycoon Secure ReplicationThis post details Cloudflare's contribution of security enhancements for data replication in the open-source Kyoto Tycoon project. Specifically, Cloudflare added mutually-authenticated TLS encryption for data transit between data centers, preventing man-in-the-middle attacks and protecting sensitive data. They have released this code back to the open-source community, demonstrating their commitment to open source collaboration and improving the security of widely used infrastructure components.
  21. Introducing lua-capnproto: better serialization in LuaIntroduced lua-capnproto, a new open-source Lua module for Cap'n Proto serialization and deserialization. This module provides high-performance data transfer capabilities for Lua applications, addressing the need for efficient serialization within Cloudflare's NGINX/Lua stack and for inter-data center communication. The post details installation, Cap'n Proto definition, data preparation, and usage examples for serialization and deserialization, along with performance comparisons to lua-cjson.
  22. Keeping our open source promiseThis post details Cloudflare's continued commitment to open source by highlighting the release and updates of several new projects: Red October (two-man rule for secrets), Lua Resty Shcache (shared cache for OpenResty/Nginx Lua), Lua Resty Core (new FFI-based Lua API for ngx_lua), Go Libs (small Go libraries), BM (Go implementation of Bentley-McIlroy compression), Lua Raven (Lua interface for Sentry), Lua Resty Logger Socket (non-blocking logger for Nginx Lua), conf (Go configuration file parser), Lua Resty Kyoto Tycoon (non-blocking Lua interface for Kyoto Tycoon), Go LZ4 (Go package for LZ4 compression), Aho Corasick (Go package for Aho-Corasick string matching), kt-fdw (Postgres foreign data wrapper for Kyoto Tycoon), Lua Resty Cookie (Lua Resty package for Cookie handling), and Docker NPMJS (Docker image for private npmjs repository). It also mentions contributions to OpenSSL, SystemTap, and PhantomJS, and employee contributions to the Nginx changelog. The post also notes the reorganization of the Cloudflare GitHub page by language/software and announces an upcoming security project.
  23. Red October: CloudFlare’s Open Source Implementation of the Two-Man RuleThis post details the open-sourcing of 'Red October,' a Go-based service implementing the 'two-man rule' for enhanced data security against insider threats. It highlights Cloudflare's commitment to sharing security innovations with the community by releasing the technology under a BSD license and making it available on GitHub, encouraging its adoption and further development by others.
  24. CloudFlare And Open Source Software: A Two-Way StreetThis post details Cloudflare's philosophy and practice of engaging with open source software. It highlights the company's reliance on open source projects like nginx, PostgreSQL, and Kyoto Tycoon, and its contributions back to the community through releasing its own open source tools (e.g., golog, lua-cmsgpack, CNAME flattener) and hiring developers to work on critical open source projects (e.g., ngx_lua module, TLS Session Ticket keys for nginx). It also mentions sponsoring LuaJIT for performance improvements. The post emphasizes the benefits of open sourcing modifications, such as the 'many eyeballs' effect and reducing fork costs, and expresses a long-term goal of open-sourcing all major components.