Ah, nvm. Figured it out. Taking a look at one of the test cases in Klaxon helped out ❤️ https://github.com/cbeust/klaxon/blob/f9b77efd98fb4fa405d1f6736f30de72b3b6cf63/klaxon/src/test/kotlin/com/beust/klaxon/Issue229Test.kt