At Dext (dext.com), we use a perky Ruby style – we omit the parentheses in method calls. When I joined the company we enforced this rule through code review. Having spent time in Go-land where gofmt rules every discussion, I wondered... How hard it is to make RuboCop enforce calls without parens? Turns out – it's pretty hard! Ruby hides a lot of ambiguities and requirements in that permissive syntax. Join me, in a talk where I explore every little Ruby quirk I found while trying to invent a robot that yells at me when I call a method with parens instead of a Human!