Apache Traffic Server

A fast, scalable and extensible HTTP/1.1 and HTTP/2 compliant caching proxy server.

Powering major CDNs and content providers worldwide, serving multiple terabits per second of traffic.

Download Now Documentation

$ cmake --preset release # ATS 10+

$ cmake --build build-release --target install

$ /opt/ats/bin/trafficserver start

✓ Traffic Server running

Overview

Caching

Improve your response time, while reducing server load and bandwidth needs by caching and reusing frequently-requested web pages, images, and web service calls.

Proxying

Easily add keep-alive, filter or anonymize content requests, or add load balancing by adding a proxy layer.

Fast

Scales well on modern SMP hardware, handling 10s of thousands of requests per second.

Extensible

APIs to write your own plug-ins to do anything from modifying HTTP headers to handling ESI requests to writing your own cache algorithm.

Proven

Battle-tested at scale, powering multiple terabits per second of traffic at major CDNs and content providers worldwide. Visit our Customers page for more users.

Modern Protocols

Full support for HTTP/1.1 and HTTP/2, with ongoing development for emerging web standards and protocols.

Learn More

Get Support

Having trouble with builds or configurations? Subscribe to our Users Mailing List or join #traffic-server on ASF Slack (request an invite on users@).
Questions about the ATS code? Get help from developers on our dev discussion list.
Report or confirm bugs on our GitHub Issues.

Get Involved

Subscribe and help out on the users Mailing List or join #traffic-server on ASF Slack.
Report issues or bring patches to our GitHub repo.
We've tagged github issues that have a low entrance barrier.

Web Resources

Read the Administrator's Guide for installation, configuration, and operations.
Check out the Developer's Guide for plug-in development and internals.
Use the Via Header Decoder to parse and debug ATS Via headers.

News

August 13, 2025

The first minor version of ATS 10 is released: v10.1.0!

June 17, 2025

We are releasing version v10.0.6 and v9.2.11 which include security fixes and improvements. We recommend everyone to upgrade to one of these versions of ATS.

April 2, 2025

We are releasing version v10.0.5 and v9.2.10 which include security fixes and improvements. We recommend everyone to upgrade to one of these versions of ATS.

March 5, 2025

We are releasing version v10.0.4 and v9.2.9 with several bugfixes and improvements.

January 31, 2025

We are releasing version 9.2.8 with several bugfixes and improvements.

January 31, 2025

We are releasing version 10.0.3 with several bugfixes and improvements.

November 26, 2024

We are releasing version v9.2.7 with several bugfixes.

November 12, 2024

We are releasing version v10.0.2 and v9.2.6 with several bugfixes and improvements.

View All Releases