Introducing MOQ5: Open-Source C Library with MOQ Support for Both Ingest and Egress

MOQ5 gives developers a reusable foundation for building live streaming workflows with Media over QUIC Transport (MOQT). This open-source native C library supports both sending and receiving media, helping teams move from experimenting with MOQ to creating practical applications and infrastructure.

In this blog, you will learn:

• What MOQ5 is and why Red5 built it,
• How its transport-independent architecture works,
• Which applications and infrastructure can use it,
• Where to find the project and start exploring it.

What is MOQ5?

MOQ5 is an open-source native C library designed to provide reusable MOQ infrastructure for applications, relays, publishers, players, encoders, and content delivery networks. It gives developers a flexible protocol foundation for integrating MOQT into different products and runtime environments without tying the core library to a particular networking stack.

I’m excited to share that Ray Lucke, Red5 Senior Software Architect, has open-sourced MOQ5, a native C library for Media over QUIC Transport (MOQT), with support for both sending and receiving media. You can find it in the OpenMOQ Software Consortium’s GitHub organization here: https://github.com/openmoq/moq5

If you prefer video format, watch my recent #ChrisAllenTalks video, where I cover:

• What MOQ5 is and why we built it
• Who can benefit from it
• How it can be used in emerging MOQ workflows
• Where to find the project and get started
• What’s next as we continue expanding its capabilities alongside OpenMOQ Software Consortium members, including Qualabs, YouTube, Bitmovin, and others.

If you would like to dive deeper into the technical details of MOQ5, continue reading.

MOQ5 is built as reusable MOQ infrastructure for applications, relays, publishers, players, encoders, and CDNs. At its core, it is a sans-I/O MOQT protocol engine: it focuses on session state, message encoding and decoding, subscription management, track and object handling, protocol negotiation, and transport-independent logic.

That separation is intentional. The core protocol logic is independent of sockets, TLS stacks, QUIC implementations, threads, and event loops. Applications and adapters provide the actual transport integration, which makes MOQ5 easier to embed across different products and runtime environments, and easier to test for interoperability.

The project also includes transport adapters and a higher-level media service tier, so developers can build real media workflows without having to start from raw protocol primitives. While we originally focused heavily on application-facing media workflows, the same architecture is also valuable for server-side infrastructure like relays and CDN components. We’re already using MOQ5 inside Red5’s MOQ work.

We’re continuing to add functionality and harden this open-source library, and we’re already working with OpenMOQ members including Qualabs, YouTube, and Bitmovin as the ecosystem takes shape. I’m looking forward to seeing what other developers build with it as well. In the end, success won’t be measured by how many people talk about MOQ. It will be measured by how many real applications and infrastructure deployments are built on top of it.

If you’re building streaming infrastructure today, how do you see MOQ fitting into your stack? Would MOQ5 be useful to you? Reach out if you’d like to get involved as a user, tester, or contributor.

Conclusion

MOQ5 provides an open-source, transport-independent C foundation for developers building MOQT applications, media workflows, relays, and CDN infrastructure. With support for both sending and receiving media, it can help teams test emerging workflows today and contribute to a growing interoperable MOQ ecosystem. Learn why this library is the open-source foundation for MOQ hardware support.

If you’ve got some use cases that want to implement live MOQ streaming, contact us using this link.