“If you are [not]” serves a different function than “unless.” “Unless” is a conjunction, and its presence creates a double negative with the end of the sentenc

“If you are [not]” serves a different function than “unless.” “Unless” is a conjunction, and its presence creates a double negative with the end of the sentence making the sentence extra clunky (“unless you’re a Ruby dev, you shouldn’t read this article.”) A few iterations later, we get to the correct syntax, “read this article if you’re a Ruby dev.”