Anyone with inside knowledge of Firestore care to comment on the ETA of more advanced query functionality?

We have played with Firestore quite a bit, but rely heavily on the ability to do aggregate queries. Reading all of the documents and performing this on the client side is nowhere near good enough. Nor is triggering functions to update a "count" or "sum" property on a doc.

Edit: Looks like a PM answered on another thread...

"It's a point of internal discussion on scalable ways to achieve this, but nothing we can promise. We definitely see the need for it."