[the_watcher]

Rails isn't dying, it's just a lot less difficult to hire Rails programmers, as it's brought Ruby mainstream enough that nearly all software engineers have either learned it or are more than capable of learning it. The "hottest" programming languages right now seem to be the various JS frameworks. If you are looking for highest paying, I doubt the old standards of C, C++, Java, C#, etc. will lose their place as the most reliable ways to make money as a software engineer.

Another change is that more and more startups are launching with just a mobile app, meaning Swift, Obj-C, and Java will be in demand.