Internal, distributed message queue. Main communication happens via port 4730 and consists of simple json messages. Completely independent of the main website back-end. Gearman
Internal Jezebel functionality, not directly exposed to the client. Part of the internal search scoring, main communication happens via binary port 9300. Elasticsearch
Main data storage. Any writes to Couchbase auto-replicate to Elasticsearch (via XDRC) and from there on propagate into the internal Jezebel pipeline via opes. Couchbase