As a Javascript Developer, which language would you advise to diversify my skills ?

Hi there,

I consider myself as an experienced Javascript developer (7+ years of experience), but still learning a lot every single day. These days I focus on React and React Native and have some experience with nodeJS too. Typescript is probably the next thing I want to try with GraphQL.

That said, I feel the need to diversify my skills and learn a new language. But I want to do it the smart way: my plan is to move in the coming years from Europe to Canada with my little family, and I would like to be able to reach companies which might not need a Frontend developer full-time.

I obviously tried a lot of language in my career so far, but never deeply enough to call myself efficient (except maybe Ruby), so I would like to know if some of you could advise me or share with the community your experiences with others languages.

Main points for me would be:

• being able to reach a wide range of projects/companies. This point is important as I prefer to be efficient in fewer languages, but having a deep understanding of them.
• playing well with Javascript (or completing it)
• not too obscure/difficult (as a father, I would rather use my nights to sleep)
• having a nice future and community
• and fun to use!

My candidates so far (but open to others):

• C#
• Kotlin
• Elixir (although I do not see very often positions requiring this language, which is too bad 'cause I really love functional programming)
• Golang
• Python (I have to admit that I got quickly bored with this one, but might give another shot)

Thanks a lot for your help. I know majority of answers could start with "it depends", but please keep in mind I am not looking for the best or most performant language, but simply the one allowing me to diversify my skills while enjoying the learning process.