The ears are pure German shepherd, but I’ve never seen a shepherd mix without at least a little bit of the German shepherd markings. The fur is pure golden retriever, but I’ve never seen a golden mix with fully erect ears. From the expression, I’d suspect him of being a husky or malamute mix, and the ears are similar-ish, but the fur just seems so odd…
Also, the expression looks happy and mellow, but the tail is tucked so far down you can barely tell it's there at all.