No worries!

Niko's talk should probably be the reference material, but you definitely can deploy new queries interactively, against maintained indexed representations of the historical streams. No recompilation required. Streams are maintained in indexed form and don't need to be re-flowed (they may need to be re-indexed if your query calls for an index that doesn't exist).

Deploying a new query takes ~milliseconds if the correct indices exist, and if not it seems to be no slower than purpose-built Datalog systems (e.g. LogicBlox, but performance seems solid compared with Souffle). This is despite then running against live-updated data.

As I suspect you know, we cannot report performance relative to Datomic. ;)