Combine hoisin and Sriracha in a small bowl; mix well with a fork.
Place a steamer in water in a stir-fry wok; bring water to a boil.
Place salmon on the steamer and baste with hoisin mixture. Cover and cook until fish flakes easily with a fork, 7 to 10 minutes. Transfer salmon to a plate; remove steamer.
Empty water and heat oil in the wok over high heat. Add stir-fry vegetables with any leftover hoisin mixture; cook until tender, about 5 minutes. Serve with salmon.