After upgrading graphql-kotlin from 5.5.0 to 6.1.0 I get

Exception com.expediagroup.graphql.generator.exceptions.TypeNotSupportedException: Cannot convert kotlin.Array<kotlin.Double> since it is not a valid GraphQL type or outside the supported packages

on initialization. Is this type really no longer supported or is something else wrong? Is there a way to get a bit more information from the schema generator?

Arrays are no longer supported as we cannot get appropriate type information at runtime. It was a casualty of dropping Jackson that solved duplicate serialization issue

you can fix it by using

List<Double>

we solved it by providing it a scalar with a

.coercing

but that only works in some cases.. we use ktx-serialization to serialize/deserialize that data since long ago.. and because we really want to avoid copying into a different datastructure just for graphql and back, as this is a type provided by a dependency...