ktor: Simple code straight from documentation returns ERR_EMPTY_RESPONSE

Using 0.9.3 (current version) I tried the following simple code from the documentation:

fun main(args: Array<String>) {
 val s = embeddedServer(Netty, port = 8080) {
        routing {
            get("/") {
                call.respondText("Hello World!", ContentType.Text.Plain)
            }
            get("/demo") {
                call.respondText("HELLO WORLD!")
            }
        }
    }
    s.start(wait = true)
}

When I run this code I see:

238 [main] INFO ktor.application - No ktor.deployment.watch patterns specified, automatic reload is not active
290 [main] INFO ktor.application - Responding at http://0.0.0.0:8080

When I visit http://localhost:8080/ in my browser I get ERR_EMPTY_RESPONSE. Adding a println() at the beginning of the get("/") block reveals that it doesn’t seem to be executing any of that code at all.

I’m currently using ktor in a separate project which doesn’t suffer from this problem - I’ve got no idea what’s different between one and the other. Would appreciate any ideas.