@marpaia (sorry for joining the party a little late, was on the road), the bulk of our extension is quite like the core (or what you have described)..there is no pub/sub however..the events are cached locally in a extension-specific-rocksdb, whose life cycle is maintained by the extension..depending on the type of events (and the volume), having pub/sub across core-extensions could really stress out the thrift IPC..its mostly stable but it has its limits..