Interesting; I&#x27;d love to read _what_ exactly they send in those long HTTP requests.<p>I&#x27;d think something along the lines of Surrogate Keys&#x2F;Cache Tags would make sense:<p>- <a href="https:&#x2F;&#x2F;www.drupal.org&#x2F;developing&#x2F;api&#x2F;8&#x2F;cache&#x2F;tags" rel="nofollow">https:&#x2F;&#x2F;www.drupal.org&#x2F;developing&#x2F;api&#x2F;8&#x2F;cache&#x2F;tags</a><p>- <a href="http:&#x2F;&#x2F;info.varnish-software.com&#x2F;blog&#x2F;advanced-cache-invalidation-strategies" rel="nofollow">http:&#x2F;&#x2F;info.varnish-software.com&#x2F;blog&#x2F;advanced-cache-invalid...</a> (ugh, they broke their site, cached at <a href="https:&#x2F;&#x2F;pinboard.in&#x2F;cached&#x2F;a31c4630dd2d&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pinboard.in&#x2F;cached&#x2F;a31c4630dd2d&#x2F;</a>)<p>- <a href="https:&#x2F;&#x2F;www.fastly.com&#x2F;blog&#x2F;surrogate-keys-part-1" rel="nofollow">https:&#x2F;&#x2F;www.fastly.com&#x2F;blog&#x2F;surrogate-keys-part-1</a><p>- <a href="https:&#x2F;&#x2F;blog.cloudflare.com&#x2F;introducing-a-powerful-way-to-purge-cache-on-cloudflare-purge-by-cache-tag&#x2F;" rel="nofollow">https:&#x2F;&#x2F;blog.cloudflare.com&#x2F;introducing-a-powerful-way-to-pu...</a>