[burnallofit]

Not to knock your experience, but imho C, Python, and Javascript are the BASIC of modern programming languages. (I don't know about Go).

Additionally, there are different levels of knowing a language. You can write perfectly workable programs in C without ever touching function pointers. So what's your level of mastery?

And then there are more difficult languages. Have you tried C++ or Scala? Ever explored the esoterical intricacies of Java's type system? Lisp? Objective-C? Kotlin? ADA?

Ok, that's languages. How about parallelism? Massive parallelism? Tight resource constraints such as limited memory? Error handling? Modern language and compiler design?

I'm not trying to say you need to know all these things to be a decent coder. My point is there are many harder problems out there and maybe if you're bored you might want to try working on some of them.