1. A computer-implemented method operable on a device comprising hardware including memory and at least one processor, the method comprising: by a particular service: (A) receiving at least one event stream of event data, said event data relating to operation of at least one type of service, each event of said at least one event stream comprising: (i) a timestamp for said event, (ii) information relating to said event; and (B) producing state data relating to information represented in said event data while asynchronously responding to queries relating to said state data.