caching and cache-filling library, a replacement for memcached

 Groupcache is a caching and cache-filling library, intended as a
 replacement for memcached in many cases.
 .
 Like memcached, groupcache shards by key to select which peer is
 responsible for that key. Unlike memcached, groupcache does not
 require running a separate set of servers, comes with a cache
 filling mechanism, and contains some other useful features.