There are lots of tools and even lots of toolboxes. What do you like to do? What can you find work for? If you know other languages, you can shift easily. It

There are lots of tools and even lots of toolboxes. What do you like to do? What can you find work for? If you know other languages, you can shift easily. It's not like you have to invest years into a new language if you're already proficient with others. You're not going to forget if/else logic, what functions do, or object oriented basics. Most languages just have their own syntactic sugar on all of that. Learn Python. Learn Node. Learn Julia. Be flexible.