I was disappointed in finding out that they don't have a separate work space to build gluten-free sandwiches. The workers offered to put a piece of paper down, but couldn't guarantee cross-contamination issues at all. If you have celiac disease, this is not the place to eat. I did up going to the grocery store next-door, Balducci's, and bought my own stuff to make a sandwich.
While the Rye Ridge Deli is your quintessential NY-style deli, it is also gluten aware. All of the wait staff are aware of gluten and what on its menu is no good. The availability of GF bread (Udi's commercial) makes all of their sandwiches accessible. Sadly, they have yet to develop a GF matza ball soup. No GF workspace so for those who are ultra-sensitive, this might not be the place.