Codewars and Hackerrank do prove exactly nothing. C will likely lose to almost all the modern languages, while your mobile, your laptop, and your desktop are all running mostly C code.
I would say I [this is a personal experience, it cannot be generalized though] write Elixir 1.5 times slower than Ruby, read Elixir 2 times faster than Ruby and support/modify/refactor Elixir 20 times faster than Ruby.
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