There are some technologies that are practically guaranteed to be good investments, like becoming expert in JavaScript. You can use JavaScript on both the frontend and backend, for example.
Expect to always be retooling. Embrace it, in fact. I made a switch in my career from being an employee to being a freelance web developer. That forces me to always stay on top of things. I also think of myself as "that guy who can build you a web app" instead of a frontend or backend guy. As a consequence, I've learned frontend stuff, backend stuff, design, business dev, anything needed to get the job done.
I think it's a sign of a healthy economy that puts pressure on workers to always be updating their skills. An economy that has workers who can adapt quickly to changes in demand naturally reduces unemployment.
Expect to always be retooling. Embrace it, in fact. I made a switch in my career from being an employee to being a freelance web developer. That forces me to always stay on top of things. I also think of myself as "that guy who can build you a web app" instead of a frontend or backend guy. As a consequence, I've learned frontend stuff, backend stuff, design, business dev, anything needed to get the job done.
I think it's a sign of a healthy economy that puts pressure on workers to always be updating their skills. An economy that has workers who can adapt quickly to changes in demand naturally reduces unemployment.