The problems I see with limiting the scope to single function IO are 1. JS is dynamic and a single function can do a lot, even if you try to stub out the world

The problems I see with limiting the scope to single function IO are 1. JS is dynamic and a single function can do a lot, even if you try to stub out the world. 2. from a product perspective it would be hard to communicate what is going on. 3. Perhaps console logs could cover a lot of these cases. Does that make sense? What are you thinking of? --- We definitely want to make it easy to visualize function calls (inputs/outputs). For instance, - see outlier function arguments (the time the first param was null) or the function returned early... - see outlier call sites (the time when the function was called from a different call site) - see outlier timings (the time when the function called when some other state was null or a promise was pending) i.e. race detection On the other side, we would love to help users see the impact of a function call. For instance, - program slicing: the other code that was run because this function was invoked - data tainting: the data that was either read or written to because this function was invoked