Most of the high-level items on the rapidly growing https://docs.opendatakit.org site are user-facing, but there are developer docs (e.g. OpenRosa, JavaRosa) also there.
I think this can be a bit confusing for users because you are looking at Aggregate, Briefcase, Collect, Form Building, then all of a sudden, OpenRosa!
One option is to move more developer facing docs under a Development section (or something similar)? I haven't thought this all the way through but wanted to start a discussion!