Stop being lazy, go back to engineering first principles and it makes little sense to stay with Nix. Guix or any rewrite as a library in a well-developed language* makes more sense.
*For example, why are Haskellians using Nix so much instead of integrating its concepts into their own tooling?
Stop being lazy, go back to engineering first principles and it makes little sense to stay with C. [Insert systems programming language du jour] or any other well-developed language makes more sense.