As well as enabling great web experiences for users with high-performance content delivery, developers love Varnish Cache because of its flexibility. Varnish Configuration Language helps you write policies that dictate how incoming and outgoing requests, cached objects and data retrieved from the origin server are handled and lets you optimize it to suit your exact requirements. You can also extend Varnish Cache capabilities with additional modules. For a complete feature list, go here.
An optimized, hardened and supported version of Varnish Cache is also available. Varnish Enterprise adds significant features to the open-source technology, for organizations needing to optimize their content delivery for robustness and performance in order to stay competitive at scale. Additional support is available for getting the most out of Varnish Enterprise, which also has long-term support and managed release processes. Running Varnish Enterprise in the cloud is just as easy as running the Varnish Cache image. It features the same platform, workflow and billing methods while leveraging superior performance and a multitude of enhancements, without any backwards compatibility risks.
Help is provided through community documentation, IRC channels and forums. https://www.varnish-cache.org/support/
Enterprise-level support is available if you upgrade to Varnish Enterprise and through an additional subscription. Read here about support services or contact sales@varnish-software.com for more details. System documentation is available here.