Fastly VCL is a domain-specific programming language which has evolved from the Varnish proxy cache, which is part of Fastly's platform architecture. Varnish Enterprise VCL, instead, is specific to the Varnish Software solutions. There are some architectural similarities between Varnish Cache open source, Fastly and Varnish Enterprise, but as it is said, the devil’s in the details, hence this blog post.

Caching is good. What if, though, you could increase caching efficiency by letting some objects through the net, and not caching them as they are requested?

This is the thinking behind a new feature in the latest release of Varnish Enterprise that allows object misses to be counted via utils.backend_misses().

In a recent webinar, we shared some of the big dos and don’ts of Varnish use. After outlining the don’ts in an earlier blog post, we promised to follow up with a rundown of the five Varnish dos as presented in the webinar. Obviously, you should watch the webinar to get the full story on why and how you should take these actions in Varnish, but here’s a quick taster to give you a preview of what you’ll learn.

Over time, the most popular content we’ve created relates to hands-on Varnish use and relevant dos and don’ts. Naturally, we continue to create more content about this because our raison d’être is to help Varnish users get the maximum performance and efficiency they can from their Varnish setups.

Let’s get down to business.