A handful of good cnc engineering services images I found:
Blackened steel stair with stainless treads
Image by Caliper Studio
Center stringer comfort stair connects two office floors in Starret Lehigh constructing. Stringer and slab edge assemblies are blackened. Twenty four stainless steel treads are welded to the stringer form a continuous ribbon. 1 1/4" diameter handrail posts are continuous bent "C" shapes that wrap about treds and are welded to stringer. Stair will be delivered to site in a single piece [24′ lengthy 3′ wide 3′ tall @ 2000lbs].
Design and style by Diller Scofidio + Renfro
Detailing, Fabrication and Installation by Caliper Studio. Caliper Studio engaged Eckersley O’Callaghan & partners for engineering services.