You kind of don't need them in Ruby, because everything is a method or an object or a closure and you can dynamically create and alter those at runtime. That's why Ruby is really good for ad-hoc DSLs in ways that Rust and Swift really are not.

Crystal don't have the dynamicity but has macros to get the next best thing. Most meta magic in Ruby in good code are done at startup anyhow so you don't miss out on that much. YMMV.

> because everything is a method or an object or a closure

well, except for pattern matching. That is just syntax.