If you want a serious answer, the three big areas to focus on are web (front & backend), mobile (ios and android), and devops. For each of these areas I’ll list the most popular tech stacks. If you study any of them I would say you will pretty comfortably be able to find at least one job listing for each of these stacks pretty much anywhere in the country. And each one will virtually pay the same. Pay differences is much more dependent on the company than the tech stack
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For frontend, the king is currently and will most likely remain React. Second place would be Vue and then Angular in third. Svelte looks very promising but it’s still very new and immature so I wouldn’t focus on it just yet.
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For backend, the major players are going to be Java/Spring, C#/dotnet, Javascript/Express, Go, and PHP/Laravel. There are also some more niche jobs in a few different functional languages (Scala, Clojure, Elixir, Erlang, etc) but I wouldn’t count on those.
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For mobile it’s super easy. Swift if you’re iOS and Kotlin if you’re Android.
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For devops, I don’t feel I’m qualified enough to give an answer so I will refrain.
I will echo the other serious comments that you shouldn't overly focus on specific tech stacks. Most of the knowledge between these stacks is interchangeable as long as you have a solid CS foundation. I just wanted to give an up to date list of a few stacks that I know are going to remain popular for the foreseeable future.