Scaling or not is really up to whether people use good algorithms for problems. Obviously, if you use a dumb O(n^2) algorithm when an nlogn or an n algorithm would've worked, things will get unusably slow quite quickly. But that is as much of a problem in rails as it is anywhere else. Of course, if the framework itself provides slow algorithms, then it's silly, but it's in their best interest to do it right, and fast. Other than that, the difference between frameworks and lack thereof is in the constants, which means that throwing more hardware at the problem can overcome a "bad" (i.e. slow framework.)