@Terry4, which pump again are you using, and what is the maximum temp basal it allows?
I just checked this on the Omnipod in thinking about how well a system like Loop could manage the whole shebang WITHOUT having to explicitly ever bolus. There’s a setting for capping the maximum basal rate, which affects what can be constructed in a basal program, and what can be set for temp basals.
This tops out at 30 U/hr (WOW!), which it turns out is the largest bolus the system will let you deliver in a single bolus. I rarely (can’t even remember a time) deliver a bolus that large for a meal or correction, nor do I deliver really large boluses like that (say, 20-30 U) more than once in an hour anyway, so the basal delivery method seems more than capable to handle any BOLUS need in a hypothetical Loop or APS system that worked with Omnipod.
As such, seems the system could be designed to handle bolus needs as well, by just entering the carbs into Loop (which it sounds like you already can), and having the system just deliver the “bolus” over the next hour. Heck, it could do it even faster with the ability to deliver at a rate up to 30U/hr… A 10U bolus could be delivered in 20 minutes by cranking up to the 30U/hr rate for 20 minutes, then dropping back down to the nominal basal rate.
The idea here is something I don’t think Loop does right now, based on what I’ve read in this discussion (admittedly scant data). That is, simulate a bolus by immediately turning the insulin to “full on” until the bolus amount has been delivered, then turning it back down to the nominal basal. Then, also, reacting differently to rising BG than it would otherwise assuming you are in “fasting mode”, accounting for the IOB from the bolus in deciding what to do about the elevated BG.
So, based on the maximum parameters of the pump(s) that already work with Loop, the fact that control is achieved through tinkering with the temp basal rates may be inconsequential in terms of handling boluses as well. If the temp basal rate capability is high enough, seems to me the bolus side of the AP is doable right now, with the system you’re using (in theory – someone would have to figure it out and write the code).
Hope that was clear… kind of complicated gendanken