So in one of my worlds, I have come of with a very odd social structure that most of the 'urban' societies use.

Nearly every person is a member of a Gens (plural Gentes, semi-placeholder name) A Gens is an extended family-of-families who are specialized into a particular economic sphere, and who live and work together. The vast majority of trade occurs between Gens as units rather than between individuals, and nearly all property is owned at the Gens level.

Gentes all have their own unique internal governance systems, but broadly speaking, most of the small ones are direct democracies with no specific leader, while the larger ones have a pecking-order based on seniority, either by age or by accomplishing certain feats in their respective craft. Size-wise, Gentes range in size from a hundred or so members at the lower end to a thousand or so at the higher end. A hundred or so is a small as you can get an remain economically viable, while at the larger end you tend to either bleed membership or split into smaller Gentes outright.

For example, Gens Hlautren are a Gens of stone-workers and architects who design and build the various structures in the city. Their children are trained from a fairly young age in the various skills needed for the profession. When one of the other Gentes needs a building built, they will commission Hlautren (or another Gens in he same industry) for the task.

You are technically permitted to leave your current Gens at any time, but if no other Gens will take you in, you are screwed. If you leave, you leave with your skills and the clothes on your back (if they let you keep even that). Again, property is owned at the Gens level, and independent wage-work isn't really a thing in this setting, so if you are not a member of a Gens, you can't even buy food. However, it is not uncommon for two or more Gentes to deliberately trade members in certain cases, like when a new batch of children come of age and some develop interests or talents outside the Gens' sphere.

I am still fleshing this out and developing it, so I came to ask. Is there anything, real or fictional, even vaguely similar to this social structure? The placeholder name came from a Roman concept, but has little resemblance to the current version. It is kind of like a Guild (and in fact evolved out of them in-universe) but not. It is kind of like a Caste system, but not- too much inter-factional mobility and the lack of a fixed hierarchy. It is vaguely like a clan-system transplanted into an urban environment, but not. Anarcho-syndicalist communes are tenuously similar, but the coupling of economic activity to kinship is a major divergence.

The only fictional examples that I can think of are the Kiith of the Homeworld franchise (but smaller, and in an otherwise very different setting) and the Factions of Divergent (but actually workable as a functional society)

Anything similar-ish that I could use for inspiration? This seems like I made something so off-the-wall and specific that resources seem thin on the ground.