Awesome stuff - this is the kind of high-level thinking I love to see. I think your "do one thing and do it well" focus is commendable, and the subjective choices you've taken to get there are all A+ to me. This isn't turning out to be a very useful comment but wanted to let you know that someone who's also thinking about abstract frameworks for agent ensembles thinks you're right on the money.

A bit busy right now but will probably try to contribute if I can! I know very little about the low-level workings of Python and whatever the "GIL" is, but my single-process ensemble ended up using `AsyncIO` instead of `Thread` because of difficulty running a Flask server in a child thread; do you know if that would fix your CPU blocking concerns? Mostly asking so I know if I have the same problems and just haven't discovered them yet lol

One very subjective opinion: The README is great but very long - I would consider putting either/both of the code samples from the bottom at the top, so someone experienced with the basic concepts can take a quick look and understand the gist immediately. Your language at the top is of course all accurate, but it's such an abstract project that even an accurate description leaves a lot of questions, IMO.

P.S. I can't believe you got the github username "operand" that's sick