It's interesting. Ant is a somewhat constrained imperative language. Gradle is a highly constrained declarative language built on top of, and with an escape hatch to, a completely unconstrained imperative language.

If you stay within the bounds of that the Gradle DSL can do, rather than throwing Groovy around (which is possible - i write a lot of Gradle, and very rarely write raw Groovy), then Gradle is rather nice and easy to reason about. But if you don't, well, you're going to have a bad time.