Convesio uses a semi-proprietary caching implementation featuring 3 distinct layers of caching. Layer 1 (L1) of the caching resides at our load balancer layer. Layer 2 (L2) uses NGINX microcaching. Layer 3 (L3) runs inside each container with the PHP runtime of the site and utilizes Varnish.
L1 decides what will be stored on L2 and L3, based on the number of request an assets received and number of time it has been modified, during those request. This implementation enables intelligent caching that is aware of content changes at the container level and distributes load to optimize performance.
*L1 and L2 are in production with L3 scheduled for release in the near future.