I don't think the Nix language requires understanding of functional programming. Overall, it's not so different from JSON. What is different is that it provides

I don't think the Nix language requires understanding of functional programming. Overall, it's not so different from JSON. What is different is that it provides a few programming language constructs on top like variables, functions, and conditionals. This enables developers using the Nix language to properly abstract complex configurations in a comprehensible way, thus avoiding the pitfalls of writing JSON and YAML by hand.