It’s rare to find a distillery that does everything on-site, from scratch. It’s an extremely difficult endeavor to accomplish, considering all of the labor it takes to produce grains, mill, malt, store them, and then take all that hard work and magically turn it into whiskey, which then needs to be aged and stored, etc.
https://thewhiskeywash.com/reviews/whiskey-review-hillrock-double-cask-rye/