The recycler caste was one of the most ancient and numerous roles in society, second only to the weavers themselves. These webbers spent their time moving through the network, listening for the telltale changes in pitch that indicated strain or sundering. Their task was not a simple one. Broken threads often impinged on others, causing collateral disruption. There were many different kinds of breaks: tears, splits, unravels, anchor and junction breaks, surface snaps, and the trickiest of all, the axial breaks; some weren't even breaks at all but a sort of slackening or sclerosis.

The weaver caste had separated eons ago into multiple sub-castes such as fixer-casters, stringers, braiders, netters, knotters, repairers, and builders. With leg-tools resembling fishing poles, casters specialized in hitting a solid target with a line weighted with a sticky end-dollop. Along with good aim, casting required a knowledge of how to deal with different surfaces. Once the anchor lines were in place, stringers, knotters, and framers would create the structural grid to which weavers would attach various lines, meshes, and sheets.

The hunting caste was separated into casting and netting types. Hunters took pride in their quick reflexes and stamina while farmers tended to be more deliberate and methodical. While most webber thread contained a natural fungicide, certain types were prone to mold. At some point in their history, webbers had discovered that one kind of mold was edible and begun to cultivate it in large amounts. The fungal fuzz could be skimmed right off the thread with the right leg-tools. Although simple in principle, it took practice to scoop up as much film as possible without straining or snapping the thread. Once harvested, the fungus was collected into silk bags and hung to dry. The end result had a crumbly, cauliflower-like consistency that was rich in nutrition. It was the main staple of webber societies, and the word for it was translated into English as just "bread."

Engineers were near the top of the caste hierarchy. While they enjoyed more privileges and pride of place in cities, they also shouldered a heavy burden. When a web sagged or an anchor line snapped, it was the engineers' fault. When a webber fell to their death due to a structural failure, an engineer would have to answer for it.

The ruling caste was the highest of all, and its trial was like no other. Rulers did not rely on leg-tools and physical skills but on deftness of mind. When a webber reached the age of trial, they would be put through a mental gauntlet of questions. Only one webber in a hundred would be selected. Selection was only the first stage. There were multiple levels of rulers that culminated in a high council.