Announcing River: A High Performance and Memory Safe Reverse Proxy Built on Pingora

Josh Aas
Feb 28, 2024

Today we are announcing plans to build a new high performance and memory safe reverse proxy in partnership with Cloudflare, Shopify, and Chainguard. The new software will be built on top of Cloudflare's Pingora, a Rust-based HTTP proxy, the open sourcing of which was announced today.

Just about every significant deployment on the Internet makes use of reverse proxy software, and the most commonly deployed reverse proxy software is not memory safe. This means that most deployments have millions of lines of C and C++ handling incoming traffic at the edges of their networks, a risk that needs to be addressed if we are to have greater confidence in the security of the Internet. In order to change this, Prossimo is investing in new reverse proxy software called River, which will offer excellent performance while reducing the chance of memory safety vulnerabilities to near zero.

“Cloudflare announced plans to open source Pingora, a high performance, memory-safe framework to build large scale networked systems a little over a year ago. After the announcement, it became clear that we were not the only ones striving to replace unsafe legacy Internet infrastructure,” said Aki Shugaeva, Engineering Director, Cloudflare. “Cloudflare's mission is to help build a better Internet and we look forward to partnering with the ISRG and others on the River project to continue to improve the Internet for everyone.”

At Shopify, we support the efforts to improve the efficiency of crucial web traffic handling infrastructure for a safer and faster HTTP routing system. We appreciate Cloudflare's contribution on this front through the open-sourcing of Pingora, providing the project with a solid foundation to build upon.

Mike Shaver, Distinguished Engineer at Shopify

ISRG contracted with James Munns over the past few months to lead an effort with our partners to create an architecture and engineering plan, which can be viewed here.

Some of the most compelling features include:

  • Better connection reuse than proxies like Nginx due to a multithreading model, which greatly improves performance.

  • WASM-based scriptability means scripting will be performant and River will be scriptable in any language that can compile to WASM.

  • Simple configuration, as we've learned some lessons from configuring other software for the past couple of decades.

  • It's written in Rust so you can deploy without worrying about memory safety issues.

The engineering work to implement is expected to begin in Q2 2024.

Building a piece of software like this is no small task and we recognize the ambition it will take. We're grateful for the help we've gotten from our partners so far. “Chainguard is proud to support and promote the use of memory safe software, and Prossimo's new reverse proxy, River, is a powerful step forward in securing critical parts of our collective Internet infrastructure,” said Dan Lorenc, CEO of Chainguard. “We commend the Cloudflare team for their open source contribution of the Pingora framework and ISRG's continued work to help developers everywhere build with more memory safe technologies and eliminate entire classes of these vulnerabilities.”

If you or your organization are interested in contributing engineering hours or financial support to help us get there, please reach out to to begin the conversation.