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kotlinlang

The main purpose of IO is to suspend side effects so they can be evaluated at the edge. A suspend function invoking another suspend function is still pure because there is guarantees neither of those function can be invoked within a pure function unless in the context of the IO continuation that Fx provides.
If anything suspend composition is not stack safe by default but again, Kotlin allows `tailrec` in suspend functions and Arrow Fx automatically trampolines if needed as you use `!` or `flatMap`