Usually a workflow engine will come with a DSL (https://en.wikipedia.org/wiki/Domain-specific_language). My point here is that you can use instead a General Purpose Language such as Kotlin here, as long as you use it with special provided functions (here `proxy`, `async`) and an interpreter (such as Infinitic). The engine you obtain is much versative and powerful than usual workflow engines. For examples, I can use map, loop, and so other data manipulation instructions of the language. I can also manipulate input and output of tasks natively