I think I get my package right?

If you’re on version 1.2 then there’s been an issue reported about this. Try taking out the parameters

testing:Boolean = false

from the

Application.module function

. See this issue for more details https://github.com/ktorio/ktor/issues/1132

tried it our, still same error...

Well my guess is in your application.conf file, you’re referencing

ApplicationKt.main

which isn’t present in the picture you posted but rather you have an

ApplicationKt.module

method. Try replacing the main with module in the Hocon file application.conf