The performance related bits: - Handcrafted SQL. - Reduce memory usage, e.g. use mutable map. - Aggressive caching with layers of caches, DB result cache, ap

The performance related bits: - Handcrafted SQL. - Reduce memory usage, e.g. use mutable map. - Aggressive caching with layers of caches, DB result cache, app level object cache, and HTTP cache. Some DB queries are partitioned and each partitioned result is cached in key-value store.