[winrid]

We had our own database as a service thing that used ES and MongoDB. All teams used that service. Basically you would define your schema using the Thrift API and the service provided CRUD operations AND aggregations. This was a Java shop.

Scaling writes just meant changing that service's implimentation. We wrote them to Mongo and synched them to ES. There are much better ways to do that, but ES would be overloaded w/ just 500 writes a second so it didn't matter.