Okay, I got the main function into a more testable state, in a low-effort way that I can confirm didn't break the script endpoint. My plan is to get application code to full coverage, then start translating my plans for interfaces into test updates. Hopefully, this will all translate to a second prototype within a few weeks.
Other stuff that's happening... Well, Pijul's infrastructure is apparently shored up enough now, because it's under active development, as of, like a few days ago, up through a few hours ago. I've got some interface changes I want to try out, but I think it makes sense to wait for a release; there is all kinds of stuff going on in there.
Anything else? Mostly, I need rest, so I'll try to wrap up now.