Thanks @petter. Yes I’m reading v2 and was still confused 
It does seem that my app’s simple filtering is happening server side, I don’t think I see data going back and forth…I just see the data at beginning of workflow, ~5 seconds of no data movement, and then a bunch at the end. So I presume the workflows are happening server side as I desire.
I wish someone would expand upon your description of how to use DevTools for Bubble 
. I don’t know of any other resources on that topic. I don’t know what I’m looking at in there.
BTW to add to the filter confusion: you CAN do Advanced Filters on the server, via Backend Workflow. I haven’t tried it, maybe it’s not recommended.
Looking forward to v3 of the book! So much about Bubble is still unwritten…for example you can’t Schedule an API Workflow from inside a Custom Element but the error checker won’t catch it.
I’m grateful for these forums