You're talking sense, but I'm kinda wanting to do it at the subprocess level so that caller and callee need not use the same language (I was talking in terms of

You're talking sense, but I'm kinda wanting to do it at the subprocess level so that caller and callee need not use the same language (I was talking in terms of tests but tests are just a special kind of function). Whether to use nodejs or python or rust (and which version thereof) will be as much a part of the bundled function as its code. I figure I'll wrap nix so it can replicate the environments, then I'll just have to do the runtime stuff.