Archaeology has turned up a number of sources - vestiges of workshops, tools, and raw materials - that tell us in varying degrees about the craftspeople that worked in Saint-Denis.
The oldest such indication of production on the site of the basilica is a pin-making workshop waste from which were found in a ditch from the last third of the fourth century ; from them, we can see the various stages in manufacturing pins from bone.
Craftsmanship in the Early Middle Ages was distinguished by a great mastery of metalworking. In the late sixth or early seventh century, belt buckles were mass-produced in a founder's workshop located at the edge of the necropolis. Not far from this workshop, three smelting furnaces smelting furnaces reveal the existence of a forge, whose working life was probably short.
Scraps from a leather workshop, discovered in the filled-in ditches of the Carolingian castellum may have come from the monastery's shoe-maker's workshop, which we know about from written sources.
A waste pit, excavated to the north of the monumental complex, was found to contain scraps from a workshop that, around the year 1000, assembled or restored glass-windows.