[cloverich]

> mobx needs to walk all your store objects and check for changes, on top of what React does.

I don't think that is quite correct. I think it keeps a mapping of observed properties and which React components rely on them. Then, changing any property becomes a lookup (not a walk) of who is observering, and a `forceRender` on the results. So if no components are observing the property, there's no further computation. Its not "on top of what React does" because it short-circuits it (like useMemo) -- except you don't have to hand-craft any useMemo comparators, it does that for you by tracking which properties you access.