HTTP Headers that Make Your Website Go Faster

Wednesday, 11 October, 2023 - 11:0011:40

Thijs Feryn, Varnish Software


Slowdowns can be the death of any web. These problems, which often happen during traffic spikes, have a detrimental effect on the user experience and can result in loss of customers.

Fortunately, there are some simple and effective techniques to mitigate the impact of traffic spikes – however, most developers aren’t using these techniques to their full potential: caching HTTP responses.

While there are many caching implementations out there, HTTP already has conventional caching mechanisms built into the protocol, which are respected by most caching systems.

In this presentation, the audience will learn how to leverage some of those built-in mechanisms and apply them to a reverse caching proxy. The caching proxy that is featured in this presentation is Varnish Cache.

The audience will learn how to control the lifetime of cached objects, create cache variations, perform conditional requests, handle stale data, revalidate expired content, handle errors, and use HTTP placeholders.

Thijs Feryn, Varnish Software

As the Technical Evangelist at Varnish Software, Thijs Feryn focuses on web performance, software scalability, and content delivery. He demonstrates content-driven and technical messaging through presentations, videos, books, blog posts, social media posts, podcasts, and other media.

Thijs is a published author and wrote Getting Started with Varnish Cache and Varnish 6 by Example. As a public speaker, he has a track record of over 290 presentations in 22 different countries, where he is often praised for his energetic and engaging presentation style.

As an evangelist, Thijs is also active in many open-source communities, most notably the Varnish and PHP community. He has contributed to various communities for almost 20 years both technically and as an organizer and facilitator.

For more information, please visit -

@conference {292082,
author = {Thijs Feryn},
title = {{HTTP} Headers that Make Your Website Go Faster},
year = {2023},
address = {Dublin},
publisher = {USENIX Association},
month = oct

Presentation Video