It will all depend on the ingredients in your au jus mix and your buttermilk ranch dressing mix. But, yes, this roast should be keto-friendly. It's typically served over mashed potatoes or rice. So, if you are trying to keep this recipe low carb, you might want to serve it as is with a low carb vegetable on the side. Or, you could serve it over mashed cauliflower if you prefer.