If you have these skills there is a very high likelihood that you can do most other things that are thrown at you
Most of the other answers have all these high level wishy washy specifications, I thought I’d take a more brass tacks approach.
I suppose this list could be called necessary but not sufficient. The question is what does a master “look like”. If you can only work with one or two languages you are by no means a master.
If you have these skills there is a very high likelihood that you can do most other things that are thrown at you
Most of the other answers have all these high level wishy washy specifications, I thought I’d take a more brass tacks approach.