Doesn't need to be `Iterable` itself, but only implicitly `Iterable` (as is `Option`).  In fact, what I believe Patrick was suggesting is that `tachyonStore` be made into an `Option` so that the common Scala idiom of `anOption.foreach(doSomethingIfSome(_))` can be used.  Even without changing the type of `tachyonStore`, a form of this idiom can be used anywhere `!= null` is used (but that's not a stylistic quirk that we've adopted consistently): `Option(tachyonStore).foreach(_.doSomething)`