Oh interesting. So in a sense you are passing the "dependency's response" as a parameter _to_ `Process`, and thus removing the need to mock a dependency in orde

Oh interesting. So in a sense you are passing the "dependency's response" as a parameter _to_ `Process`, and thus removing the need to mock a dependency in order to induce an erroring dependency-response - you can instead _create_ a payload that resembles an erroring dependency-response, and then directly test "when `Process` is called with `BadPayload`, it should respond as follows". Neat - thanks!