Varnish Modules (VMODs)
VMODs are extensions written for Varnish Cache that extend VCL capabilities. Bundled modules include blob (binary data handling), cookie (HTTP cookie parsing), directors (load balancing strategies), h2 (HTTP/2 control), proxy (PROXY protocol support), purge (cache purging), std (standard utility functions), and unix (Unix socket support). Additional community VMODs are available for headers, digest, auth, and more.