Hi: if I got a function like

fun doSomeStuff() : Deferred<String> = async { /*doing something*/}

, should that be an extension function of a

coroutineContext

as it starts a coroutine?

Yes, extension function for CoroutineContext is right solution, but in general this approach is not recommended, better to use suspend function and allow user of it wrap to async if some concurrent calls are required

would

suspend fun doSomeStuff() = withContext {}

be better, that doesn't launch a coroutine but changes the context of the existing one, right?

Yes, suspend + wittContext is recommended way See for instance this article https://medium.com/@elizarov/blocking-threads-suspending-coroutines-d33e11bf4761

great, thanks